8.1. "datetime" --- Tipos básicos de data e hora
************************************************

**Código Fonte:** Lib/datetime.py

======================================================================

O módulo "datetime" fornece classes para manipular datas e tempo de
forma simples ou complexas. Apesar de cálculos aritméticos com data e
tempo serem suportados, o foco da implementação está na extração
eficiente de atributo para formatar resultados e manipulação. Para
funcionalidades relacionadas, veja também os módulos  "time" e
"calendar".

There are two kinds of date and time objects: "naive" and "aware".

An aware object has sufficient knowledge of applicable algorithmic and
political time adjustments, such as time zone and daylight saving time
information, to locate itself relative to other aware objects.  An
aware object is used to represent a specific moment in time that is
not open to interpretation [1].

A naive object does not contain enough information to unambiguously
locate itself relative to other date/time objects.  Whether a naive
object represents Coordinated Universal Time (UTC), local time, or
time in some other timezone is purely up to the program, just like it
is up to the program whether a particular number represents metres,
miles, or mass.  Naive objects are easy to understand and to work
with, at the cost of ignoring some aspects of reality.

For applications requiring aware objects, "datetime" and "time"
objects have an optional time zone information attribute, "tzinfo",
that can be set to an instance of a subclass of the abstract "tzinfo"
class. These "tzinfo" objects capture information about the offset
from UTC time, the time zone name, and whether Daylight Saving Time is
in effect.  Note that only one concrete "tzinfo" class, the "timezone"
class, is supplied by the "datetime" module.  The "timezone" class can
represent simple timezones with fixed offset from UTC, such as UTC
itself or North American EST and EDT timezones.  Supporting timezones
at deeper levels of detail is up to the application.  The rules for
time adjustment across the world are more political than rational,
change frequently, and there is no standard suitable for every
application aside from UTC.

O módulo "datetime" exporta as seguintes constantes:

datetime.MINYEAR

   O menor número de ano permitido no objeto :classe`date` ou
   :classe`.datetime`  . :const`MINYEAR` é "1".

datetime.MAXYEAR

   O maior número de ano permitido no objeto :classe`date` ou
   :classe`.datetime` . :const`MAXYER` é "9999".

Ver também:

  Módulo "calendar"
     Funções gerais relacionadas ao calendário.

  Módulo "time"
     Acesso de hora e conversões.


8.1.1. Tipos disponíveis
========================

class datetime.date

   Uma data ingênua idealizada, assumindo que o atual calendário
   Gregoriano sempre foi, e sempre estará em vigor. Atributos: "year",
   "month", e "day".

class datetime.time

   An idealized time, independent of any particular day, assuming that
   every day has exactly 24*60*60 seconds (there is no notion of "leap
   seconds" here). Attributes: "hour", "minute", "second",
   "microsecond", and "tzinfo".

class datetime.datetime

   Uma combinação de uma data e uma hora. Atributos: "ano", "mês",
   "dia", "hora", "minuto", "segundo", "microsegundo", e "tzinfo".

class datetime.timedelta

   Uma duração que expressa a diferença entre duas instâncias "date",
   "time" ou "datetime" para resolução de microssegundos.

class datetime.tzinfo

   An abstract base class for time zone information objects.  These
   are used by the "datetime" and "time" classes to provide a
   customizable notion of time adjustment (for example, to account for
   time zone and/or daylight saving time).

class datetime.timezone

   Uma classe que implementa a classe base abstrata
   >>:classe:`tzinfo`<< como um deslocamento fixo do UTC.

   Novo na versão 3.2.

Objetos desses tipos são imutáveis.

Objetos do tipo: classe`date` são sempre ingênuos.

An object of type "time" or "datetime" may be naive or aware. A
"datetime" object *d* is aware if "d.tzinfo" is not "None" and
"d.tzinfo.utcoffset(d)" does not return "None".  If "d.tzinfo" is
"None", or if "d.tzinfo" is not "None" but "d.tzinfo.utcoffset(d)"
returns "None", *d* is naive.  A "time" object *t* is aware if
"t.tzinfo" is not "None" and "t.tzinfo.utcoffset(None)" does not
return "None".  Otherwise, *t* is naive.

The distinction between naive and aware doesn't apply to "timedelta"
objects.

Relacionamentos de subclasses:

   object
       timedelta
       tzinfo
           timezone
       time
       date
           datetime


8.1.2. "timedelta" Objetos
==========================

O objeto "timedelta" representa uma duração, a diferença entre duas
datas ou horas.

class datetime.timedelta(days=0, seconds=0, microseconds=0, milliseconds=0, minutes=0, hours=0, weeks=0)

   All arguments are optional and default to "0".  Arguments may be
   integers or floats, and may be positive or negative.

   Only *days*, *seconds* and *microseconds* are stored internally.
   Arguments are converted to those units:

   * Um milissegundo é convertido em 1000 microssegundos.

   * Um minuto é convertido em 60 segundos.

   * Uma hora é convertida em 3600 segundos.

   * Uma semana é convertida para 7 dias.

   e dias, segundos e microssegundos são normalizados para que a
   representação seja única, com

   * "0 <= microsegundos < 1000000"

   * "0 <= seconds < 3600*24" (o número de segundos em um dia)

   * "-999999999 <= dias <= 999999999"

   If any argument is a float and there are fractional microseconds,
   the fractional microseconds left over from all arguments are
   combined and their sum is rounded to the nearest microsecond using
   round-half-to-even tiebreaker.  If no argument is a float, the
   conversion and normalization processes are exact (no information is
   lost).

   Se o valor normalizado de dias estiver fora do intervalo indicado,
   "OverflowError" é gerado.

   Note that normalization of negative values may be surprising at
   first. For example,

   >>> from datetime import timedelta
   >>> d = timedelta(microseconds=-1)
   >>> (d.days, d.seconds, d.microseconds)
   (-1, 86399, 999999)

Class attributes are:

timedelta.min

   O mais negativo objeto "timedelta", "timedelta(-999999999)".

timedelta.max

   O mais positivo objeto "timedelta", "timedelta(days=999999999,
   hours=23, minutes=59, seconds=59, microseconds=999999)".

timedelta.resolution

   A menor diferença possível entre objetos não iguais "timedelta",
   "timedelta(microseconds=1)".

Observe que, devido à normalização, "timedelta.max" >
"-timedelta.min". "-timedelta.max" não é representável como um objeto
"timedelta".

Atributos de instância (somente leitura):

+--------------------+----------------------------------------------+
| Atributo           | Valor                                        |
|====================|==============================================|
| "days"             | Entre -999999999 e 999999999 inclusive       |
+--------------------+----------------------------------------------+
| "seconds"          | Entre 0 e 86399 inclusive                    |
+--------------------+----------------------------------------------+
| "microseconds"     | Entre 0 e 999999 inclusive                   |
+--------------------+----------------------------------------------+

Operações suportadas:

+----------------------------------+-------------------------------------------------+
| Operação                         | Resultado                                       |
|==================================|=================================================|
| "t1 = t2 + t3"                   | Soma de *t2* e *t3*. Depois *t1*-*t2* == *t3* e |
|                                  | *t1*-*t3* == *t2* são verdadeiros. (1)          |
+----------------------------------+-------------------------------------------------+
| "t1 = t2 - t3"                   | Diferença de *t2* e *t3*. Depois *t1* == *t2* - |
|                                  | *t3* e *t2* == *t1* + *t3* são verdadeiros      |
|                                  | (1)(6)                                          |
+----------------------------------+-------------------------------------------------+
| "t1 = t2 * i ou t1 = i * t2"     | Delta multiplicado por um número inteiro.       |
|                                  | Depois *t1* // i == *t2* é verdadeiro, desde    |
|                                  | que "i != 0".                                   |
+----------------------------------+-------------------------------------------------+
|                                  | Em geral, *t1* * i == *t1* * (i-1) + *t1* é     |
|                                  | verdadeiro. (1)                                 |
+----------------------------------+-------------------------------------------------+
| "t1 = t2 * f or t1 = f * t2"     | Delta multiplicado por um float, ponto          |
|                                  | flutuante. O resultado é arredondado para o     |
|                                  | múltiplo mais próximo de timedelta.resolution   |
|                                  | usando a metade da metade para o par.           |
+----------------------------------+-------------------------------------------------+
| "f = t2 / t3"                    | Division (3) of *t2* by *t3*.  Returns a        |
|                                  | "float" object.                                 |
+----------------------------------+-------------------------------------------------+
| "t1 = t2 / f or t1 = t2 / i"     | Delta dividido por um float ou um int. O        |
|                                  | resultado é arredondado para o múltiplo mais    |
|                                  | próximo de timedelta.resolution usando a metade |
|                                  | da metade para o par.                           |
+----------------------------------+-------------------------------------------------+
| "t1 = t2 // i" or "t1 = t2 //    | The floor is computed and the remainder (if     |
| t3"                              | any) is thrown away.  In the second case, an    |
|                                  | integer is returned. (3)                        |
+----------------------------------+-------------------------------------------------+
| "t1 = t2 % t3"                   | O restante é calculado como um objeto           |
|                                  | "timedelta". (3)                                |
+----------------------------------+-------------------------------------------------+
| "q, r = divmod(t1, t2)"          | Calcula o quociente e o restante: "q = t1 //    |
|                                  | t2" (3) e "r = t1% t2". q é um número inteiro e |
|                                  | r é um objeto "timedelta".                      |
+----------------------------------+-------------------------------------------------+
| "+t1"                            | Retorna um objeto "timedelta"  com o mesmo      |
|                                  | valor. (2)                                      |
+----------------------------------+-------------------------------------------------+
| "-t1"                            | equivalente a "timedelta"(-*t1.days*,           |
|                                  | -*t1.seconds*, -*t1.microseconds*), e a *t1**   |
|                                  | -1. (1)(4)                                      |
+----------------------------------+-------------------------------------------------+
| "abs(t)"                         | equivalente a + *t* quando "t.days> = 0", e a - |
|                                  | *t* quando "t.days <0". (2)                     |
+----------------------------------+-------------------------------------------------+
| "str(t)"                         | Retorna uma string no formato "[D day[s],       |
|                                  | ][H]H:MM:SS[.UUUUUU]", onde D é negativo para   |
|                                  | "t" negativo. (5)                               |
+----------------------------------+-------------------------------------------------+
| "repr(t)"                        | Returns a string in the form                    |
|                                  | "datetime.timedelta(D[, S[, U]])", where D is   |
|                                  | negative for negative "t". (5)                  |
+----------------------------------+-------------------------------------------------+

Notas:

1. This is exact, but may overflow.

2. This is exact, and cannot overflow.

3. A divisão por 0 gera "ZeroDivisionError".

4. -*timedelta.max* não é representável como um objeto "timedelta".

5. String representations of "timedelta" objects are normalized
   similarly to their internal representation.  This leads to somewhat
   unusual results for negative timedeltas.  For example:

   >>> timedelta(hours=-5)
   datetime.timedelta(-1, 68400)
   >>> print(_)
   -1 day, 19:00:00

6. A expressão "t2 - t3" sempre será igual à expressão "t2 + (-t3)"
   exceto quando t3 for igual a "timedelta.max"; nesse caso, o
   primeiro produzirá um  resultado enquanto o último transbordará.

In addition to the operations listed above "timedelta" objects support
certain additions and subtractions with "date" and "datetime" objects
(see below).

Alterado na versão 3.2: Floor division and true division of a
"timedelta" object by another "timedelta" object are now supported, as
are remainder operations and the "divmod()" function.  True division
and multiplication of a "timedelta" object by a "float" object are now
supported.

Comparisons of "timedelta" objects are supported with the "timedelta"
object representing the smaller duration considered to be the smaller
timedelta. In order to stop mixed-type comparisons from falling back
to the default comparison by object address, when a "timedelta" object
is compared to an object of a different type, "TypeError" is raised
unless the comparison is "==" or "!=".  The latter cases return
"False" or "True", respectively.

"timedelta" objects are *hashable* (usable as dictionary keys),
support efficient pickling, and in Boolean contexts, a "timedelta"
object is considered to be true if and only if it isn't equal to
"timedelta(0)".

Métodos de instância:

timedelta.total_seconds()

   Return the total number of seconds contained in the duration.
   Equivalent to "td / timedelta(seconds=1)".

   Observe que, em intervalos de tempo muito grandes (mais de 270 anos
   na maioria das plataformas), esse método perde a precisão de
   microssegundos.

   Novo na versão 3.2.

Example usage:

>>> from datetime import timedelta
>>> year = timedelta(days=365)
>>> another_year = timedelta(weeks=40, days=84, hours=23,
...                          minutes=50, seconds=600)  # adds up to 365 days
>>> year.total_seconds()
31536000.0
>>> year == another_year
True
>>> ten_years = 10 * year
>>> ten_years, ten_years.days // 365
(datetime.timedelta(3650), 10)
>>> nine_years = ten_years - year
>>> nine_years, nine_years.days // 365
(datetime.timedelta(3285), 9)
>>> three_years = nine_years // 3;
>>> three_years, three_years.days // 365
(datetime.timedelta(1095), 3)
>>> abs(three_years - ten_years) == 2 * three_years + year
True


8.1.3. "date" Objetos
=====================

A "date" object represents a date (year, month and day) in an
idealized calendar, the current Gregorian calendar indefinitely
extended in both directions.  January 1 of year 1 is called day number
1, January 2 of year 1 is called day number 2, and so on.  This
matches the definition of the "proleptic Gregorian" calendar in
Dershowitz and Reingold's book Calendrical Calculations, where it's
the base calendar for all computations.  See the book for algorithms
for converting between proleptic Gregorian ordinals and many other
calendar systems.

class datetime.date(year, month, day)

   All arguments are required.  Arguments may be integers, in the
   following ranges:

   * "MINYEAR <= year <= MAXYEAR"

   * "1 <= month <= 12"

   * "1 <= day <= number of days in the given month and year"

   Se um argumento fora desses intervalos for fornecido, "ValueError"
   é levantado.

Outros construtores, todos os métodos de classe.

classmethod date.today()

   Return the current local date.  This is equivalent to
   "date.fromtimestamp(time.time())".

classmethod date.fromtimestamp(timestamp)

   Return the local date corresponding to the POSIX timestamp, such as
   is returned by "time.time()".  This may raise "OverflowError", if
   the timestamp is out of the range of values supported by the
   platform C "localtime()" function, and "OSError" on "localtime()"
   failure. It's common for this to be restricted to years from 1970
   through 2038.  Note that on non-POSIX systems that include leap
   seconds in their notion of a timestamp, leap seconds are ignored by
   "fromtimestamp()".

   Alterado na versão 3.3: Levanta "OverflowError" ao invés de
   "ValueError" se o carimbo de data/hora estiver fora do intervalo de
   valores suportados pela plataforma C "localtime()" função. Levanta
   "OSError" ao invés de "ValueError" em falha de "localtime()" .

classmethod date.fromordinal(ordinal)

   Return the date corresponding to the proleptic Gregorian ordinal,
   where January 1 of year 1 has ordinal 1.  "ValueError" is raised
   unless "1 <= ordinal <= date.max.toordinal()". For any date *d*,
   "date.fromordinal(d.toordinal()) == d".

Atributos de classe:

date.min

   A data representável mais antiga, "date(MINYEAR, 1, 1)".

date.max

   A data representável mais tardia, "date(MAXYEAR, 12, 31)".

date.resolution

   A menor diferença possível entre objetos date não iguais,
   "timedelta(days=1)".

Atributos de instância (somente leitura):

date.year

   Entre "MINYEAR" e "MAXYEAR" incluindo extremos.

date.month

   Entre 1 e 12 incluindo extremos.

date.day

   Entre 1 e o número de dias no mês especificado do ano especificado.

Operações suportadas:

+---------------------------------+------------------------------------------------+
| Operação                        | Resultado                                      |
|=================================|================================================|
| "date2 = date1 + timedelta"     | *date2* is "timedelta.days" days removed from  |
|                                 | *date1*.  (1)                                  |
+---------------------------------+------------------------------------------------+
| "date2 = date1 - timedelta"     | Computa *date2* de modo que "date2 + timedelta |
|                                 | == date1". (2)                                 |
+---------------------------------+------------------------------------------------+
| "timedelta = date1 - date2"     | (3)                                            |
+---------------------------------+------------------------------------------------+
| "date1 < date2"                 | *date1* é considerada menor que *date2*        |
|                                 | quando *date1* precede *date2* no tempo. (4)   |
+---------------------------------+------------------------------------------------+

Notas:

1. *date2* is moved forward in time if "timedelta.days > 0", or
   backward if "timedelta.days < 0".  Afterward "date2 - date1 ==
   timedelta.days". "timedelta.seconds" and "timedelta.microseconds"
   are ignored. "OverflowError" is raised if "date2.year" would be
   smaller than "MINYEAR" or larger than "MAXYEAR".

2. "timedelta.seconds" e "timedelta.microseconds" são ignoradas.

3. This is exact, and cannot overflow.  timedelta.seconds and
   timedelta.microseconds are 0, and date2 + timedelta == date1 after.

4. In other words, "date1 < date2" if and only if "date1.toordinal() <
   date2.toordinal()". Date comparison raises "TypeError" if the other
   comparand isn't also a "date" object. However, "NotImplemented" is
   returned instead if the other comparand has a "timetuple()"
   attribute.  This hook gives other kinds of date objects a chance at
   implementing mixed-type comparison. If not, when a "date" object is
   compared to an object of a different type, "TypeError" is raised
   unless the comparison is "==" or "!=".  The latter cases return
   "False" or "True", respectively.

Dates can be used as dictionary keys. In Boolean contexts, all "date"
objects are considered to be true.

Métodos de instância:

date.replace(year=self.year, month=self.month, day=self.day)

   Return a date with the same value, except for those parameters
   given new values by whichever keyword arguments are specified.  For
   example, if "d == date(2002, 12, 31)", then "d.replace(day=26) ==
   date(2002, 12, 26)".

date.timetuple()

   Return a "time.struct_time" such as returned by "time.localtime()".
   The hours, minutes and seconds are 0, and the DST flag is -1.
   "d.timetuple()" is equivalent to "time.struct_time((d.year,
   d.month, d.day, 0, 0, 0, d.weekday(), yday, -1))", where "yday =
   d.toordinal() - date(d.year, 1, 1).toordinal() + 1" is the day
   number within the current year starting with "1" for January 1st.

date.toordinal()

   Return the proleptic Gregorian ordinal of the date, where January 1
   of year 1 has ordinal 1.  For any "date" object *d*,
   "date.fromordinal(d.toordinal()) == d".

date.weekday()

   Retorna o dia da semana como um inteiro, onde Segunda é 0 e Domingo
   é 6. Por exemplo, "date(2002, 12, 4).weekday() == 2", uma Quarta-
   feira. Veja também "isoweekday()".

date.isoweekday()

   Retorna o dia da semana como um inteiro, onde Segunda é 1 e Domingo
   é 7. Por exemplo, "date(2002, 12, 4).isoweekday() == 3", uma
   Quarta-feira. Veja também "weekday()", "isocalendar()".

date.isocalendar()

   Return a 3-tuple, (ISO year, ISO week number, ISO weekday).

   The ISO calendar is a widely used variant of the Gregorian
   calendar. See
   https://www.staff.science.uu.nl/~gent0113/calendar/isocalendar.htm
   for a good explanation.

   The ISO year consists of 52 or 53 full weeks, and where a week
   starts on a Monday and ends on a Sunday.  The first week of an ISO
   year is the first (Gregorian) calendar week of a year containing a
   Thursday. This is called week number 1, and the ISO year of that
   Thursday is the same as its Gregorian year.

   For example, 2004 begins on a Thursday, so the first week of ISO
   year 2004 begins on Monday, 29 Dec 2003 and ends on Sunday, 4 Jan
   2004, so that "date(2003, 12, 29).isocalendar() == (2004, 1, 1)"
   and "date(2004, 1, 4).isocalendar() == (2004, 1, 7)".

date.isoformat()

   Return a string representing the date in ISO 8601 format, 'YYYY-MM-
   DD'.  For example, "date(2002, 12, 4).isoformat() == '2002-12-04'".

date.__str__()

   Para um objeto "date" *d*, "str(d)" é equivalente a
   "d.isoformat()".

date.ctime()

   Return a string representing the date, for example "date(2002, 12,
   4).ctime() == 'Wed Dec 4 00:00:00 2002'". "d.ctime()" is equivalent
   to "time.ctime(time.mktime(d.timetuple()))" on platforms where the
   native C "ctime()" function (which "time.ctime()" invokes, but
   which "date.ctime()" does not invoke) conforms to the C standard.

date.strftime(format)

   Retorna uma string representando a data, controlado por uma string
   explícita de formatação. Códigos de formatação referenciando horas,
   minutos ou segundos irão ver valores 0. Para uma lista completa de
   diretivas de formatação, veja Comportamento de strftime() e
   strptime().

date.__format__(format)

   O mesmo que "date.strftime()". Isso torna possível especificar uma
   string de formatação para o objeto "date" em literais de string
   formatados e ao usar "str.format()". Para uma lista completa de
   diretivas de formatação, veja Comportamento de strftime() e
   strptime().

Exemplo de contagem de dias para um evento:

   >>> import time
   >>> from datetime import date
   >>> today = date.today()
   >>> today
   datetime.date(2007, 12, 5)
   >>> today == date.fromtimestamp(time.time())
   True
   >>> my_birthday = date(today.year, 6, 24)
   >>> if my_birthday < today:
   ...     my_birthday = my_birthday.replace(year=today.year + 1)
   >>> my_birthday
   datetime.date(2008, 6, 24)
   >>> time_to_birthday = abs(my_birthday - today)
   >>> time_to_birthday.days
   202

Example of working with "date":

   >>> from datetime import date
   >>> d = date.fromordinal(730920) # 730920th day after 1. 1. 0001
   >>> d
   datetime.date(2002, 3, 11)
   >>> t = d.timetuple()
   >>> for i in t:     
   ...     print(i)
   2002                # year
   3                   # month
   11                  # day
   0
   0
   0
   0                   # weekday (0 = Monday)
   70                  # 70th day in the year
   -1
   >>> ic = d.isocalendar()
   >>> for i in ic:    
   ...     print(i)
   2002                # ISO year
   11                  # ISO week number
   1                   # ISO day number ( 1 = Monday )
   >>> d.isoformat()
   '2002-03-11'
   >>> d.strftime("%d/%m/%y")
   '11/03/02'
   >>> d.strftime("%A %d. %B %Y")
   'Monday 11. March 2002'
   >>> 'The {1} is {0:%d}, the {2} is {0:%B}.'.format(d, "day", "month")
   'The day is 11, the month is March.'


8.1.4. Objetos "datetime"
=========================

A "datetime" object is a single object containing all the information
from a "date" object and a "time" object.  Like a "date" object,
"datetime" assumes the current Gregorian calendar extended in both
directions; like a time object, "datetime" assumes there are exactly
3600*24 seconds in every day.

Construtor:

class datetime.datetime(year, month, day, hour=0, minute=0, second=0, microsecond=0, tzinfo=None, *, fold=0)

   The year, month and day arguments are required.  *tzinfo* may be
   "None", or an instance of a "tzinfo" subclass.  The remaining
   arguments may be integers, in the following ranges:

   * "MINYEAR <= year <= MAXYEAR",

   * "1 <= month <= 12",

   * >>``<<1 <= day <= número de dias no mês e ano fornecidos`,

   * "0 <= hour < 24",

   * "0 <= minute < 60",

   * "0 <= second < 60",

   * "0 <= microsecond < 1000000",

   * "fold in [0, 1]".

   Se um argumento fora desses intervalos for fornecido, "ValueError"
   é levantado.

   Novo na versão 3.6: Adicionado o argumento "fold".

Outros construtores, todos os métodos de classe.

classmethod datetime.today()

   Return the current local datetime, with "tzinfo" "None". This is
   equivalent to "datetime.fromtimestamp(time.time())". See also
   "now()", "fromtimestamp()".

classmethod datetime.now(tz=None)

   Return the current local date and time.  If optional argument *tz*
   is "None" or not specified, this is like "today()", but, if
   possible, supplies more precision than can be gotten from going
   through a "time.time()" timestamp (for example, this may be
   possible on platforms supplying the C "gettimeofday()" function).

   If *tz* is not "None", it must be an instance of a "tzinfo"
   subclass, and the current date and time are converted to *tz*’s
   time zone.  In this case the result is equivalent to
   "tz.fromutc(datetime.utcnow().replace(tzinfo=tz))". See also
   "today()", "utcnow()".

classmethod datetime.utcnow()

   Return the current UTC date and time, with "tzinfo" "None". This is
   like "now()", but returns the current UTC date and time, as a naive
   "datetime" object.  An aware current UTC datetime can be obtained
   by calling "datetime.now(timezone.utc)".  See also "now()".

classmethod datetime.fromtimestamp(timestamp, tz=None)

   Retorna a data e hora local correspondente ao timestamp POSIX, como
   é retornado por "time.time()". Se o argumento opcional *tz* é
   "None" ou não especificado, o timestamp é convertido para a data e
   hora local da plataforma, e o objeto "datetime" retornado é
   ingênuo.

   If *tz* is not "None", it must be an instance of a "tzinfo"
   subclass, and the timestamp is converted to *tz*’s time zone.  In
   this case the result is equivalent to "tz.fromutc(datetime.utcfrom
   timestamp(timestamp).replace(tzinfo=tz))".

   "fromtimestamp()" may raise "OverflowError", if the timestamp is
   out of the range of values supported by the platform C
   "localtime()" or "gmtime()" functions, and "OSError" on
   "localtime()" or "gmtime()" failure. It's common for this to be
   restricted to years in 1970 through 2038. Note that on non-POSIX
   systems that include leap seconds in their notion of a timestamp,
   leap seconds are ignored by "fromtimestamp()", and then it's
   possible to have two timestamps differing by a second that yield
   identical "datetime" objects. See also "utcfromtimestamp()".

   Alterado na versão 3.3: Levanta um "OverflowError" ao invés de
   "ValueError" se o timestamp estiver fora do intervalo dos valores
   suportados pelas funções C "localtime()" ou "gmtime()" da
   plataforma. Levanta "OSError" ao invés de "ValueError" em falhas de
   "localtime()" ou "gmtime()".

   Alterado na versão 3.6: "fromtimestamp()" pode retornar instâncias
   com "fold" igual a 1.

classmethod datetime.utcfromtimestamp(timestamp)

   Return the UTC "datetime" corresponding to the POSIX timestamp,
   with "tzinfo" "None". This may raise "OverflowError", if the
   timestamp is out of the range of values supported by the platform C
   "gmtime()" function, and "OSError" on "gmtime()" failure. It's
   common for this to be restricted to years in 1970 through 2038.

   Para conseguir um objeto "datetime" consciente, chame
   "fromtiemstamp()":

      datetime.fromtimestamp(timestamp, timezone.utc)

   Nas plataformas compatíveis com POSIX, é equivalente à seguinte
   expressão:

      datetime(1970, 1, 1, tzinfo=timezone.utc) + timedelta(seconds=timestamp)

   com a exceção de que a última fórmula sempre dá suporte ao
   intervalo completo de anos: entre "MINYEAR" e "MAXYEAR" inclusive.

   Alterado na versão 3.3: Levanta "OverflowError" ao invés de
   "ValueError" se o timestamp estiver fora do intervalo de valores
   suportados pela função C "gmtime()" da plataforma. Levanta
   "OSError" ao invés de "ValueError" em caso de falha "gmtime()".

classmethod datetime.fromordinal(ordinal)

   Return the "datetime" corresponding to the proleptic Gregorian
   ordinal, where January 1 of year 1 has ordinal 1. "ValueError" is
   raised unless "1 <= ordinal <= datetime.max.toordinal()".  The
   hour, minute, second and microsecond of the result are all 0, and
   "tzinfo" is "None".

classmethod datetime.combine(date, time, tzinfo=self.tzinfo)

   Return a new "datetime" object whose date components are equal to
   the given "date" object's, and whose time components are equal to
   the given "time" object's.  If the *tzinfo* argument is provided,
   its value is used to set the "tzinfo" attribute of the result,
   otherwise the "tzinfo" attribute of the *time* argument is used.

   For any "datetime" object *d*, "d == datetime.combine(d.date(),
   d.time(), d.tzinfo)".  If date is a "datetime" object, its time
   components and "tzinfo" attributes are ignored.

   Alterado na versão 3.6: Argumento *tzinfo* adicionado.

classmethod datetime.strptime(date_string, format)

   Return a "datetime" corresponding to *date_string*, parsed
   according to *format*.  This is equivalent to
   "datetime(*(time.strptime(date_string, format)[0:6]))".
   "ValueError" is raised if the date_string and format can't be
   parsed by "time.strptime()" or if it returns a value which isn't a
   time tuple. For a complete list of formatting directives, see
   Comportamento de strftime() e strptime().

Atributos de classe:

datetime.min

   O primeiro "datetime" representável, "datetime(MINYEAR, 1, 1,
   tzinfo=None)".

datetime.max

   O último "datetime" representável, "datetime(MAXYEAR, 12, 31, 23,
   59, 59, 999999, tzinfo=None)".

datetime.resolution

   A menor diferença possível entre objetos "datetime" desiguais,
   "timedelta(microseconds=1)".

Atributos de instância (somente leitura):

datetime.year

   Entre "MINYEAR" e "MAXYEAR" incluindo extremos.

datetime.month

   Entre 1 e 12 incluindo extremos.

datetime.day

   Entre 1 e o número de dias no mês especificado do ano especificado.

datetime.hour

   No intervalo "range(24)".

datetime.minute

   No intervalo "range(60)".

datetime.second

   No intervalo "range(60)".

datetime.microsecond

   No intervalo "range(1000000)".

datetime.tzinfo

   O objeto passado como o argumento *tzinfo* do construtor
   "datetime", ou "None" se nada foi passado.

datetime.fold

   In "[0, 1]".  Used to disambiguate wall times during a repeated
   interval.  (A repeated interval occurs when clocks are rolled back
   at the end of daylight saving time or when the UTC offset for the
   current zone is decreased for political reasons.) The value 0 (1)
   represents the earlier (later) of the two moments with the same
   wall time representation.

   Novo na versão 3.6.

Operações suportadas:

+-----------------------------------------+----------------------------------+
| Operação                                | Resultado                        |
|=========================================|==================================|
| "datetime2 = datetime1 + timedelta"     | (1)                              |
+-----------------------------------------+----------------------------------+
| "datetime2 = datetime1 - timedelta"     | (2)                              |
+-----------------------------------------+----------------------------------+
| "timedelta = datetime1 - datetime2"     | (3)                              |
+-----------------------------------------+----------------------------------+
| "datetime1 < datetime2"                 | Compara um "datetime" a um       |
|                                         | "datetime". (4)                  |
+-----------------------------------------+----------------------------------+

1. datetime2 is a duration of timedelta removed from datetime1, moving
   forward in time if "timedelta.days" > 0, or backward if
   "timedelta.days" < 0.  The result has the same "tzinfo" attribute
   as the input datetime, and datetime2 - datetime1 == timedelta
   after. "OverflowError" is raised if datetime2.year would be smaller
   than "MINYEAR" or larger than "MAXYEAR". Note that no time zone
   adjustments are done even if the input is an aware object.

2. Computa o datetime2 tal que datetime2 + timedelta == datetime1.
   Assim como para adição, o resultado tem o mesmo atributo "tzinfo"
   que datetime de entrada, e nenhum ajuste de fuso horário é feito
   mesmo que a entrada seja consciente disso.

3. Subtraction of a "datetime" from a "datetime" is defined only if
   both operands are naive, or if both are aware.  If one is aware and
   the other is naive, "TypeError" is raised.

   If both are naive, or both are aware and have the same "tzinfo"
   attribute, the "tzinfo" attributes are ignored, and the result is a
   "timedelta" object *t* such that "datetime2 + t == datetime1".  No
   time zone adjustments are done in this case.

   If both are aware and have different "tzinfo" attributes, "a-b"
   acts as if *a* and *b* were first converted to naive UTC datetimes
   first.  The result is "(a.replace(tzinfo=None) - a.utcoffset()) -
   (b.replace(tzinfo=None) - b.utcoffset())" except that the
   implementation never overflows.

4. *datetime1* é considerado menor que *datetime2* quando *datetime1*
   precede *datetime2* no tempo.

   If one comparand is naive and the other is aware, "TypeError" is
   raised if an order comparison is attempted.  For equality
   comparisons, naive instances are never equal to aware instances.

   If both comparands are aware, and have the same "tzinfo" attribute,
   the common "tzinfo" attribute is ignored and the base datetimes are
   compared.  If both comparands are aware and have different "tzinfo"
   attributes, the comparands are first adjusted by subtracting their
   UTC offsets (obtained from "self.utcoffset()").

   Alterado na versão 3.3: Equality comparisons between naive and
   aware "datetime" instances don't raise "TypeError".

   Nota:

     In order to stop comparison from falling back to the default
     scheme of comparing object addresses, datetime comparison
     normally raises "TypeError" if the other comparand isn't also a
     "datetime" object.  However, "NotImplemented" is returned instead
     if the other comparand has a "timetuple()" attribute.  This hook
     gives other kinds of date objects a chance at implementing mixed-
     type comparison.  If not, when a "datetime" object is compared to
     an object of a different type, "TypeError" is raised unless the
     comparison is "==" or "!=".  The latter cases return "False" or
     "True", respectively.

"datetime" objects can be used as dictionary keys. In Boolean
contexts, all "datetime" objects are considered to be true.

Métodos de instância:

datetime.date()

   Retorna um objeto "date" com o mesmo ano, mês e dia.

datetime.time()

   Return "time" object with same hour, minute, second, microsecond
   and fold. "tzinfo" is "None".  See also method "timetz()".

   Alterado na versão 3.6: O valor attr:*.fold* é copiado ao objeto
   "time" retornado.

datetime.timetz()

   Return "time" object with same hour, minute, second, microsecond,
   fold, and tzinfo attributes.  See also method "time()".

   Alterado na versão 3.6: O valor attr:*.fold* é copiado ao objeto
   "time" retornado.

datetime.replace(year=self.year, month=self.month, day=self.day, hour=self.hour, minute=self.minute, second=self.second, microsecond=self.microsecond, tzinfo=self.tzinfo, * fold=0)

   Return a datetime with the same attributes, except for those
   attributes given new values by whichever keyword arguments are
   specified.  Note that "tzinfo=None" can be specified to create a
   naive datetime from an aware datetime with no conversion of date
   and time data.

   Novo na versão 3.6: Adicionado o argumento "fold".

datetime.astimezone(tz=None)

   Retorna um objeto "datetime" com novo atributo "tzinfo" definido
   por *tz*, ajustando a data e hora de forma que o resultado seja o
   mesmo horário UTC que *self*, mas na hora local de *tz*.

   If provided, *tz* must be an instance of a "tzinfo" subclass, and
   its "utcoffset()" and "dst()" methods must not return "None".  If
   *self* is naive, it is presumed to represent time in the system
   timezone.

   If called without arguments (or with "tz=None") the system local
   timezone is assumed for the target timezone.  The ".tzinfo"
   attribute of the converted datetime instance will be set to an
   instance of "timezone" with the zone name and offset obtained from
   the OS.

   Se "self.tzinfo" for *tz*, "self.astimezone(tz)" é igual a *self*:
   nenhum ajuste nos dados de data ou hora é realizado. Caso contrário
   o resultado é a hora local no fuso horário *tz*, representando a
   mesma hora UTC que *self*: depois "astz = dt.astimezone(tz)", "astz
   - astz.utcoffset()" terá os mesmos dados de data e hora que "dt -
   dt.utcoffset()".

   If you merely want to attach a time zone object *tz* to a datetime
   *dt* without adjustment of date and time data, use
   "dt.replace(tzinfo=tz)".  If you merely want to remove the time
   zone object from an aware datetime *dt* without conversion of date
   and time data, use "dt.replace(tzinfo=None)".

   Perceba que o método padrão "tzinfo.fromutc()" pode ser substituído
   em uma subclasse "tzinfo" para afetar o resultado retornado por
   "astimezone()". Ignorando erros de letras maiúsculas/minúsculas,
   "astimezone()" funciona como:

      def astimezone(self, tz):
          if self.tzinfo is tz:
              return self
          # Convert self to UTC, and attach the new time zone object.
          utc = (self - self.utcoffset()).replace(tzinfo=tz)
          # Convert from UTC to tz's local time.
          return tz.fromutc(utc)

   Alterado na versão 3.3: *tz* agora pode ser omitido.

   Alterado na versão 3.6: O método "astimezone()" agora pode ser
   chamado em instâncias ingênuas que presumidamente representam a
   hora local do sistema.

datetime.utcoffset()

   If "tzinfo" is "None", returns "None", else returns
   "self.tzinfo.utcoffset(self)", and raises an exception if the
   latter doesn't return "None", or a "timedelta" object representing
   a whole number of minutes with magnitude less than one day.

datetime.dst()

   If "tzinfo" is "None", returns "None", else returns
   "self.tzinfo.dst(self)", and raises an exception if the latter
   doesn't return "None", or a "timedelta" object representing a whole
   number of minutes with magnitude less than one day.

datetime.tzname()

   Se "tzinfo" for "None", retorna "None", caso contrário retorna
   "self.tzinfo.tzname(self)", levanta uma exceção se o segundo não
   retornar "None" ou um objeto string.

datetime.timetuple()

   Return a "time.struct_time" such as returned by "time.localtime()".
   "d.timetuple()" is equivalent to "time.struct_time((d.year,
   d.month, d.day, d.hour, d.minute, d.second, d.weekday(), yday,
   dst))", where "yday = d.toordinal() - date(d.year, 1,
   1).toordinal() + 1" is the day number within the current year
   starting with "1" for January 1st. The "tm_isdst" flag of the
   result is set according to the "dst()" method: "tzinfo" is "None"
   or "dst()" returns "None", "tm_isdst" is set to "-1"; else if
   "dst()" returns a non-zero value, "tm_isdst" is set to "1"; else
   "tm_isdst" is set to "0".

datetime.utctimetuple()

   If "datetime" instance *d* is naive, this is the same as
   "d.timetuple()" except that "tm_isdst" is forced to 0 regardless of
   what "d.dst()" returns.  DST is never in effect for a UTC time.

   If *d* is aware, *d* is normalized to UTC time, by subtracting
   "d.utcoffset()", and a "time.struct_time" for the normalized time
   is returned.  "tm_isdst" is forced to 0. Note that an
   "OverflowError" may be raised if *d*.year was "MINYEAR" or
   "MAXYEAR" and UTC adjustment spills over a year boundary.

datetime.toordinal()

   Return the proleptic Gregorian ordinal of the date.  The same as
   "self.date().toordinal()".

datetime.timestamp()

   Return POSIX timestamp corresponding to the "datetime" instance.
   The return value is a "float" similar to that returned by
   "time.time()".

   Naive "datetime" instances are assumed to represent local time and
   this method relies on the platform C "mktime()" function to perform
   the conversion.  Since "datetime" supports wider range of values
   than "mktime()" on many platforms, this method may raise
   "OverflowError" for times far in the past or far in the future.

   Para instâncias conscientes de "datetime", o valor retornado é
   computado como:

      (dt - datetime(1970, 1, 1, tzinfo=timezone.utc)).total_seconds()

   Novo na versão 3.3.

   Alterado na versão 3.6: O método "timestamp()" usa o atributo
   "fold" para desambiguar os tempos durante um intervalo repetido.

   Nota:

     There is no method to obtain the POSIX timestamp directly from a
     naive "datetime" instance representing UTC time.  If your
     application uses this convention and your system timezone is not
     set to UTC, you can obtain the POSIX timestamp by supplying
     "tzinfo=timezone.utc":

        timestamp = dt.replace(tzinfo=timezone.utc).timestamp()

     ou calculando o timestamp diretamente:

        timestamp = (dt - datetime(1970, 1, 1)) / timedelta(seconds=1)

datetime.weekday()

   Retorna o dia da semana como um inteiro, em que segunda-feira é 0 e
   domingo é 6. O mesmo que "self.date().weekday()". Veja também
   "isoweekday()".

datetime.isoweekday()

   Retorna o dia da semana como um inteiro, em que segunda-feira é 1 e
   domingo é 7. O mesmo que "self.date().isoweekday()". Veja também
   "weekday()", "isocalendar()".

datetime.isocalendar()

   Return a 3-tuple, (ISO year, ISO week number, ISO weekday).  The
   same as "self.date().isocalendar()".

datetime.isoformat(sep='T', timespec='auto')

   Return a string representing the date and time in ISO 8601 format,
   YYYY-MM-DDTHH:MM:SS.mmmmmm or, if "microsecond" is 0, YYYY-MM-
   DDTHH:MM:SS

   If "utcoffset()" does not return "None", a 6-character string is
   appended, giving the UTC offset in (signed) hours and minutes:
   YYYY-MM-DDTHH:MM:SS.mmmmmm+HH:MM or, if "microsecond" is 0 YYYY-MM-
   DDTHH:MM:SS+HH:MM

   The optional argument *sep* (default "'T'") is a one-character
   separator, placed between the date and time portions of the result.
   For example,

   >>> from datetime import tzinfo, timedelta, datetime
   >>> class TZ(tzinfo):
   ...     def utcoffset(self, dt): return timedelta(minutes=-399)
   ...
   >>> datetime(2002, 12, 25, tzinfo=TZ()).isoformat(' ')
   '2002-12-25 00:00:00-06:39'

   O argumento opcional *timespec* especifica o número de componentes
   adicionais do tempo a incluir (o padrão é "'auto'"). Pode ser uma
   das seguintes strings:

   * "'auto'": O mesmo que "'seconds'" se "microsecond" é 0, o mesmo
     que "'microseconds'" caso contrário.

   * "'hours'": Include the "hour" in the two-digit HH format.

   * "'minutes'": Include "hour" and "minute" in HH:MM format.

   * "'seconds'": Include "hour", "minute", and "second" in HH:MM:SS
     format.

   * "'milliseconds'": Include full time, but truncate fractional
     second part to milliseconds. HH:MM:SS.sss format.

   * "'microseconds'": Include full time in HH:MM:SS.mmmmmm format.

   Nota:

     Componentes do tempo excluídos são truncados, não arredondados.

   "ValueError" será levantado com um argumento *timespec* inválido.

   >>> from datetime import datetime
   >>> datetime.now().isoformat(timespec='minutes')
   '2002-12-25T00:00'
   >>> dt = datetime(2015, 1, 1, 12, 30, 59, 0)
   >>> dt.isoformat(timespec='microseconds')
   '2015-01-01T12:30:59.000000'

   Novo na versão 3.6: Argumento *timespec* adicionado.

datetime.__str__()

   Para uma instância "datetime" *d*, "str(d)" é equivalente a
   "d.isoformat(' ')".

datetime.ctime()

   Return a string representing the date and time, for example
   "datetime(2002, 12, 4, 20, 30, 40).ctime() == 'Wed Dec  4 20:30:40
   2002'". "d.ctime()" is equivalent to
   "time.ctime(time.mktime(d.timetuple()))" on platforms where the
   native C "ctime()" function (which "time.ctime()" invokes, but
   which "datetime.ctime()" does not invoke) conforms to the C
   standard.

datetime.strftime(format)

   Return a string representing the date and time, controlled by an
   explicit format string.  For a complete list of formatting
   directives, see Comportamento de strftime() e strptime().

datetime.__format__(format)

   Same as "datetime.strftime()".  This makes it possible to specify a
   format string for a "datetime" object in formatted string literals
   and when using "str.format()".  For a complete list of formatting
   directives, see Comportamento de strftime() e strptime().

Examples of working with datetime objects:

   >>> from datetime import datetime, date, time
   >>> # Using datetime.combine()
   >>> d = date(2005, 7, 14)
   >>> t = time(12, 30)
   >>> datetime.combine(d, t)
   datetime.datetime(2005, 7, 14, 12, 30)
   >>> # Using datetime.now() or datetime.utcnow()
   >>> datetime.now()   
   datetime.datetime(2007, 12, 6, 16, 29, 43, 79043)   # GMT +1
   >>> datetime.utcnow()   
   datetime.datetime(2007, 12, 6, 15, 29, 43, 79060)
   >>> # Using datetime.strptime()
   >>> dt = datetime.strptime("21/11/06 16:30", "%d/%m/%y %H:%M")
   >>> dt
   datetime.datetime(2006, 11, 21, 16, 30)
   >>> # Using datetime.timetuple() to get tuple of all attributes
   >>> tt = dt.timetuple()
   >>> for it in tt:   
   ...     print(it)
   ...
   2006    # year
   11      # month
   21      # day
   16      # hour
   30      # minute
   0       # second
   1       # weekday (0 = Monday)
   325     # number of days since 1st January
   -1      # dst - method tzinfo.dst() returned None
   >>> # Date in ISO format
   >>> ic = dt.isocalendar()
   >>> for it in ic:   
   ...     print(it)
   ...
   2006    # ISO year
   47      # ISO week
   2       # ISO weekday
   >>> # Formatting datetime
   >>> dt.strftime("%A, %d. %B %Y %I:%M%p")
   'Tuesday, 21. November 2006 04:30PM'
   >>> 'The {1} is {0:%d}, the {2} is {0:%B}, the {3} is {0:%I:%M%p}.'.format(dt, "day", "month", "time")
   'The day is 21, the month is November, the time is 04:30PM.'

Using datetime with tzinfo:

>>> from datetime import timedelta, datetime, tzinfo
>>> class GMT1(tzinfo):
...     def utcoffset(self, dt):
...         return timedelta(hours=1) + self.dst(dt)
...     def dst(self, dt):
...         # DST starts last Sunday in March
...         d = datetime(dt.year, 4, 1)   # ends last Sunday in October
...         self.dston = d - timedelta(days=d.weekday() + 1)
...         d = datetime(dt.year, 11, 1)
...         self.dstoff = d - timedelta(days=d.weekday() + 1)
...         if self.dston <=  dt.replace(tzinfo=None) < self.dstoff:
...             return timedelta(hours=1)
...         else:
...             return timedelta(0)
...     def tzname(self,dt):
...          return "GMT +1"
...
>>> class GMT2(tzinfo):
...     def utcoffset(self, dt):
...         return timedelta(hours=2) + self.dst(dt)
...     def dst(self, dt):
...         d = datetime(dt.year, 4, 1)
...         self.dston = d - timedelta(days=d.weekday() + 1)
...         d = datetime(dt.year, 11, 1)
...         self.dstoff = d - timedelta(days=d.weekday() + 1)
...         if self.dston <=  dt.replace(tzinfo=None) < self.dstoff:
...             return timedelta(hours=1)
...         else:
...             return timedelta(0)
...     def tzname(self,dt):
...         return "GMT +2"
...
>>> gmt1 = GMT1()
>>> # Daylight Saving Time
>>> dt1 = datetime(2006, 11, 21, 16, 30, tzinfo=gmt1)
>>> dt1.dst()
datetime.timedelta(0)
>>> dt1.utcoffset()
datetime.timedelta(0, 3600)
>>> dt2 = datetime(2006, 6, 14, 13, 0, tzinfo=gmt1)
>>> dt2.dst()
datetime.timedelta(0, 3600)
>>> dt2.utcoffset()
datetime.timedelta(0, 7200)
>>> # Convert datetime to another time zone
>>> dt3 = dt2.astimezone(GMT2())
>>> dt3     
datetime.datetime(2006, 6, 14, 14, 0, tzinfo=<GMT2 object at 0x...>)
>>> dt2     
datetime.datetime(2006, 6, 14, 13, 0, tzinfo=<GMT1 object at 0x...>)
>>> dt2.utctimetuple() == dt3.utctimetuple()
True


8.1.5. Objetos "time"
=====================

A time object represents a (local) time of day, independent of any
particular day, and subject to adjustment via a "tzinfo" object.

class datetime.time(hour=0, minute=0, second=0, microsecond=0, tzinfo=None, *, fold=0)

   All arguments are optional.  *tzinfo* may be "None", or an instance
   of a "tzinfo" subclass.  The remaining arguments may be integers,
   in the following ranges:

   * "0 <= hour < 24",

   * "0 <= minute < 60",

   * "0 <= second < 60",

   * "0 <= microsecond < 1000000",

   * "fold in [0, 1]".

   If an argument outside those ranges is given, "ValueError" is
   raised.  All default to "0" except *tzinfo*, which defaults to
   "None".

Atributos de classe:

time.min

   O "time" mais cedo que pode ser representado, "time(0, 0, 0, 0)".

time.max

   O "time" mais tardio que pode ser representado, "time(23, 59, 59,
   999999)".

time.resolution

   A menor diferença possível entre objetos "time" diferentes,
   "timedelta(microseconds=1)", embora perceba que aritmética sobre
   objetos "time" não é suportada.

Atributos de instância (somente leitura):

time.hour

   No intervalo "range(24)".

time.minute

   No intervalo "range(60)".

time.second

   No intervalo "range(60)".

time.microsecond

   No intervalo "range(1000000)".

time.tzinfo

   O objeto passado como argumento tzinfo para o construtor da classe
   "time", ou "None" se nada foi passado.

time.fold

   In "[0, 1]".  Used to disambiguate wall times during a repeated
   interval.  (A repeated interval occurs when clocks are rolled back
   at the end of daylight saving time or when the UTC offset for the
   current zone is decreased for political reasons.) The value 0 (1)
   represents the earlier (later) of the two moments with the same
   wall time representation.

   Novo na versão 3.6.

Operações suportadas:

* comparison of "time" to "time", where *a* is considered less than
  *b* when *a* precedes *b* in time.  If one comparand is naive and
  the other is aware, "TypeError" is raised if an order comparison is
  attempted. For equality comparisons, naive instances are never equal
  to aware instances.

  If both comparands are aware, and have the same "tzinfo" attribute,
  the common "tzinfo" attribute is ignored and the base times are
  compared.  If both comparands are aware and have different "tzinfo"
  attributes, the comparands are first adjusted by subtracting their
  UTC offsets (obtained from "self.utcoffset()"). In order to stop
  mixed-type comparisons from falling back to the default comparison
  by object address, when a "time" object is compared to an object of
  a different type, "TypeError" is raised unless the comparison is
  "==" or "!=".  The latter cases return "False" or "True",
  respectively.

  Alterado na versão 3.3: Equality comparisons between naive and aware
  "time" instances don't raise "TypeError".

* hash, use as dict key

* efficient pickling

In boolean contexts, a "time" object is always considered to be true.

Alterado na versão 3.5: Before Python 3.5, a "time" object was
considered to be false if it represented midnight in UTC.  This
behavior was considered obscure and error-prone and has been removed
in Python 3.5.  See bpo-13936 for full details.

Métodos de instância:

time.replace(hour=self.hour, minute=self.minute, second=self.second, microsecond=self.microsecond, tzinfo=self.tzinfo, * fold=0)

   Return a "time" with the same value, except for those attributes
   given new values by whichever keyword arguments are specified.
   Note that "tzinfo=None" can be specified to create a naive "time"
   from an aware "time", without conversion of the time data.

   Novo na versão 3.6: Adicionado o argumento "fold".

time.isoformat(timespec='auto')

   Return a string representing the time in ISO 8601 format,
   HH:MM:SS.mmmmmm or, if "microsecond" is 0, HH:MM:SS If
   "utcoffset()" does not return "None", a 6-character string is
   appended, giving the UTC offset in (signed) hours and minutes:
   HH:MM:SS.mmmmmm+HH:MM or, if self.microsecond is 0, HH:MM:SS+HH:MM

   O argumento opcional *timespec* especifica o número de componentes
   adicionais do tempo a incluir (o padrão é "'auto'"). Pode ser uma
   das seguintes strings:

   * "'auto'": O mesmo que "'seconds'" se "microsecond" é 0, o mesmo
     que "'microseconds'" caso contrário.

   * "'hours'": Include the "hour" in the two-digit HH format.

   * "'minutes'": Include "hour" and "minute" in HH:MM format.

   * "'seconds'": Include "hour", "minute", and "second" in HH:MM:SS
     format.

   * "'milliseconds'": Include full time, but truncate fractional
     second part to milliseconds. HH:MM:SS.sss format.

   * "'microseconds'": Include full time in HH:MM:SS.mmmmmm format.

   Nota:

     Componentes do tempo excluídos são truncados, não arredondados.

   "ValueError" será levantado com um argumento *timespec* inválido.

   >>> from datetime import time
   >>> time(hour=12, minute=34, second=56, microsecond=123456).isoformat(timespec='minutes')
   '12:34'
   >>> dt = time(hour=12, minute=34, second=56, microsecond=0)
   >>> dt.isoformat(timespec='microseconds')
   '12:34:56.000000'
   >>> dt.isoformat(timespec='auto')
   '12:34:56'

   Novo na versão 3.6: Argumento *timespec* adicionado.

time.__str__()

   Para um tempo *t*, "str(t)" é equivalente a "t.isoformat()".

time.strftime(format)

   Return a string representing the time, controlled by an explicit
   format string.  For a complete list of formatting directives, see
   Comportamento de strftime() e strptime().

time.__format__(format)

   Same as "time.strftime()". This makes it possible to specify a
   format string for a "time" object in formatted string literals and
   when using "str.format()".  For a complete list of formatting
   directives, see Comportamento de strftime() e strptime().

time.utcoffset()

   If "tzinfo" is "None", returns "None", else returns
   "self.tzinfo.utcoffset(None)", and raises an exception if the
   latter doesn't return "None" or a "timedelta" object representing a
   whole number of minutes with magnitude less than one day.

time.dst()

   If "tzinfo" is "None", returns "None", else returns
   "self.tzinfo.dst(None)", and raises an exception if the latter
   doesn't return "None", or a "timedelta" object representing a whole
   number of minutes with magnitude less than one day.

time.tzname()

   Se "tzinfo" for "None", retorna "None", caso contrário retorna
   "self.tzinfo.tzname(None)", ou levanta uma exceção se o último caso
   não retornar "None" ou um objeto string.

Exemplo:

>>> from datetime import time, tzinfo, timedelta
>>> class GMT1(tzinfo):
...     def utcoffset(self, dt):
...         return timedelta(hours=1)
...     def dst(self, dt):
...         return timedelta(0)
...     def tzname(self,dt):
...         return "Europe/Prague"
...
>>> t = time(12, 10, 30, tzinfo=GMT1())
>>> t                               
datetime.time(12, 10, 30, tzinfo=<GMT1 object at 0x...>)
>>> gmt = GMT1()
>>> t.isoformat()
'12:10:30+01:00'
>>> t.dst()
datetime.timedelta(0)
>>> t.tzname()
'Europe/Prague'
>>> t.strftime("%H:%M:%S %Z")
'12:10:30 Europe/Prague'
>>> 'The {} is {:%H:%M}.'.format("time", t)
'The time is 12:10.'


8.1.6. Objetos "tzinfo"
=======================

class datetime.tzinfo

   This is an abstract base class, meaning that this class should not
   be instantiated directly.  You need to derive a concrete subclass,
   and (at least) supply implementations of the standard "tzinfo"
   methods needed by the "datetime" methods you use.  The "datetime"
   module supplies a simple concrete subclass of "tzinfo", "timezone",
   which can represent timezones with fixed offset from UTC such as
   UTC itself or North American EST and EDT.

   Uma instância de (uma subclasse concreta de) "tzinfo" pode ser
   passada para os construtores de objetos "datetime" e "time". Os
   objetos time veem seus atributos como se estivessem em horário
   local, e o objeto "tzinfo" suporta métodos revelando a diferença da
   hora local a partir de UTC, o nome do fuso horário, e diferença de
   horário em horário de verão, todos relativos ao objeto date ou time
   passado para eles.

   Special requirement for pickling:  A "tzinfo" subclass must have an
   "__init__()" method that can be called with no arguments, else it
   can be pickled but possibly not unpickled again.  This is a
   technical requirement that may be relaxed in the future.

   A concrete subclass of "tzinfo" may need to implement the following
   methods.  Exactly which methods are needed depends on the uses made
   of aware "datetime" objects.  If in doubt, simply implement all of
   them.

tzinfo.utcoffset(dt)

   Return offset of local time from UTC, in minutes east of UTC.  If
   local time is west of UTC, this should be negative.  Note that this
   is intended to be the total offset from UTC; for example, if a
   "tzinfo" object represents both time zone and DST adjustments,
   "utcoffset()" should return their sum.  If the UTC offset isn't
   known, return "None".  Else the value returned must be a
   "timedelta" object specifying a whole number of minutes in the
   range -1439 to 1439 inclusive (1440 = 24*60; the magnitude of the
   offset must be less than one day).  Most implementations of
   "utcoffset()" will probably look like one of these two:

      return CONSTANT                 # fixed-offset class
      return CONSTANT + self.dst(dt)  # daylight-aware class

   Se "utcoffset()" não retorna "None", "dst()" também não deve
   retornar "None".

   A implementação padrão de "utcoffset()" levanta
   "NotImplementedError".

tzinfo.dst(dt)

   Return the daylight saving time (DST) adjustment, in minutes east
   of UTC, or "None" if DST information isn't known.  Return
   "timedelta(0)" if DST is not in effect. If DST is in effect, return
   the offset as a "timedelta" object (see "utcoffset()" for details).
   Note that DST offset, if applicable, has already been added to the
   UTC offset returned by "utcoffset()", so there's no need to consult
   "dst()" unless you're interested in obtaining DST info separately.
   For example, "datetime.timetuple()" calls its "tzinfo" attribute's
   "dst()" method to determine how the "tm_isdst" flag should be set,
   and "tzinfo.fromutc()" calls "dst()" to account for DST changes
   when crossing time zones.

   Uma instância *tz* de uma subclasse "tzinfo" que modela tanto
   horário padrão quanto horário de verão deve ser consistente neste
   sentido:

   "tz.utcoffset(dt) - tz.dst(dt)"

   must return the same result for every "datetime" *dt* with
   "dt.tzinfo == tz"  For sane "tzinfo" subclasses, this expression
   yields the time zone's "standard offset", which should not depend
   on the date or the time, but only on geographic location.  The
   implementation of "datetime.astimezone()" relies on this, but
   cannot detect violations; it's the programmer's responsibility to
   ensure it.  If a "tzinfo" subclass cannot guarantee this, it may be
   able to override the default implementation of "tzinfo.fromutc()"
   to work correctly with "astimezone()" regardless.

   Maior parte das implementações de "dst()" provavelmente irá parecer
   com um destes dois:

      def dst(self, dt):
          # a fixed-offset class:  doesn't account for DST
          return timedelta(0)

   ou

      def dst(self, dt):
          # Code to set dston and dstoff to the time zone's DST
          # transition times based on the input dt.year, and expressed
          # in standard local time.  Then

          if dston <= dt.replace(tzinfo=None) < dstoff:
              return timedelta(hours=1)
          else:
              return timedelta(0)

   A implementação padrão de "dst()" levanta "NotImplementedError".

tzinfo.tzname(dt)

   Return the time zone name corresponding to the "datetime" object
   *dt*, as a string. Nothing about string names is defined by the
   "datetime" module, and there's no requirement that it mean anything
   in particular.  For example, "GMT", "UTC", "-500", "-5:00", "EDT",
   "US/Eastern", "America/New York" are all valid replies.  Return
   "None" if a string name isn't known.  Note that this is a method
   rather than a fixed string primarily because some "tzinfo"
   subclasses will wish to return different names depending on the
   specific value of *dt* passed, especially if the "tzinfo" class is
   accounting for daylight time.

   A implementação padrão de "tzname()" levanta "NotImplementedError".

These methods are called by a "datetime" or "time" object, in response
to their methods of the same names.  A "datetime" object passes itself
as the argument, and a "time" object passes "None" as the argument.  A
"tzinfo" subclass's methods should therefore be prepared to accept a
*dt* argument of "None", or of class "datetime".

When "None" is passed, it's up to the class designer to decide the
best response.  For example, returning "None" is appropriate if the
class wishes to say that time objects don't participate in the
"tzinfo" protocols.  It may be more useful for "utcoffset(None)" to
return the standard UTC offset, as there is no other convention for
discovering the standard offset.

When a "datetime" object is passed in response to a "datetime" method,
"dt.tzinfo" is the same object as *self*.  "tzinfo" methods can rely
on this, unless user code calls "tzinfo" methods directly.  The intent
is that the "tzinfo" methods interpret *dt* as being in local time,
and not need worry about objects in other timezones.

Exste mais um método "tzinfo" que uma subclasse pode querer
substituir:

tzinfo.fromutc(dt)

   This is called from the default "datetime.astimezone()"
   implementation.  When called from that, "dt.tzinfo" is *self*, and
   *dt*'s date and time data are to be viewed as expressing a UTC
   time.  The purpose of "fromutc()" is to adjust the date and time
   data, returning an equivalent datetime in *self*'s local time.

   Most "tzinfo" subclasses should be able to inherit the default
   "fromutc()" implementation without problems.  It's strong enough to
   handle fixed-offset time zones, and time zones accounting for both
   standard and daylight time, and the latter even if the DST
   transition times differ in different years.  An example of a time
   zone the default "fromutc()" implementation may not handle
   correctly in all cases is one where the standard offset (from UTC)
   depends on the specific date and time passed, which can happen for
   political reasons. The default implementations of "astimezone()"
   and "fromutc()" may not produce the result you want if the result
   is one of the hours straddling the moment the standard offset
   changes.

   Ignorando o código para casos de erros, a implementação padrão
   "fromutc()" funciona como:

      def fromutc(self, dt):
          # raise ValueError error if dt.tzinfo is not self
          dtoff = dt.utcoffset()
          dtdst = dt.dst()
          # raise ValueError if dtoff is None or dtdst is None
          delta = dtoff - dtdst  # this is self's standard offset
          if delta:
              dt += delta   # convert to standard local time
              dtdst = dt.dst()
              # raise ValueError if dtdst is None
          if dtdst:
              return dt + dtdst
          else:
              return dt

Example "tzinfo" classes:

   from datetime import tzinfo, timedelta, datetime, timezone

   ZERO = timedelta(0)
   HOUR = timedelta(hours=1)
   SECOND = timedelta(seconds=1)

   # A class capturing the platform's idea of local time.
   # (May result in wrong values on historical times in
   #  timezones where UTC offset and/or the DST rules had
   #  changed in the past.)
   import time as _time

   STDOFFSET = timedelta(seconds = -_time.timezone)
   if _time.daylight:
       DSTOFFSET = timedelta(seconds = -_time.altzone)
   else:
       DSTOFFSET = STDOFFSET

   DSTDIFF = DSTOFFSET - STDOFFSET

   class LocalTimezone(tzinfo):

       def fromutc(self, dt):
           assert dt.tzinfo is self
           stamp = (dt - datetime(1970, 1, 1, tzinfo=self)) // SECOND
           args = _time.localtime(stamp)[:6]
           dst_diff = DSTDIFF // SECOND
           # Detect fold
           fold = (args == _time.localtime(stamp - dst_diff))
           return datetime(*args, microsecond=dt.microsecond,
                           tzinfo=self, fold=fold)

       def utcoffset(self, dt):
           if self._isdst(dt):
               return DSTOFFSET
           else:
               return STDOFFSET

       def dst(self, dt):
           if self._isdst(dt):
               return DSTDIFF
           else:
               return ZERO

       def tzname(self, dt):
           return _time.tzname[self._isdst(dt)]

       def _isdst(self, dt):
           tt = (dt.year, dt.month, dt.day,
                 dt.hour, dt.minute, dt.second,
                 dt.weekday(), 0, 0)
           stamp = _time.mktime(tt)
           tt = _time.localtime(stamp)
           return tt.tm_isdst > 0

   Local = LocalTimezone()


   # A complete implementation of current DST rules for major US time zones.

   def first_sunday_on_or_after(dt):
       days_to_go = 6 - dt.weekday()
       if days_to_go:
           dt += timedelta(days_to_go)
       return dt


   # US DST Rules
   #
   # This is a simplified (i.e., wrong for a few cases) set of rules for US
   # DST start and end times. For a complete and up-to-date set of DST rules
   # and timezone definitions, visit the Olson Database (or try pytz):
   # http://www.twinsun.com/tz/tz-link.htm
   # http://sourceforge.net/projects/pytz/ (might not be up-to-date)
   #
   # In the US, since 2007, DST starts at 2am (standard time) on the second
   # Sunday in March, which is the first Sunday on or after Mar 8.
   DSTSTART_2007 = datetime(1, 3, 8, 2)
   # and ends at 2am (DST time) on the first Sunday of Nov.
   DSTEND_2007 = datetime(1, 11, 1, 2)
   # From 1987 to 2006, DST used to start at 2am (standard time) on the first
   # Sunday in April and to end at 2am (DST time) on the last
   # Sunday of October, which is the first Sunday on or after Oct 25.
   DSTSTART_1987_2006 = datetime(1, 4, 1, 2)
   DSTEND_1987_2006 = datetime(1, 10, 25, 2)
   # From 1967 to 1986, DST used to start at 2am (standard time) on the last
   # Sunday in April (the one on or after April 24) and to end at 2am (DST time)
   # on the last Sunday of October, which is the first Sunday
   # on or after Oct 25.
   DSTSTART_1967_1986 = datetime(1, 4, 24, 2)
   DSTEND_1967_1986 = DSTEND_1987_2006

   def us_dst_range(year):
       # Find start and end times for US DST. For years before 1967, return
       # start = end for no DST.
       if 2006 < year:
           dststart, dstend = DSTSTART_2007, DSTEND_2007
       elif 1986 < year < 2007:
           dststart, dstend = DSTSTART_1987_2006, DSTEND_1987_2006
       elif 1966 < year < 1987:
           dststart, dstend = DSTSTART_1967_1986, DSTEND_1967_1986
       else:
           return (datetime(year, 1, 1), ) * 2

       start = first_sunday_on_or_after(dststart.replace(year=year))
       end = first_sunday_on_or_after(dstend.replace(year=year))
       return start, end


   class USTimeZone(tzinfo):

       def __init__(self, hours, reprname, stdname, dstname):
           self.stdoffset = timedelta(hours=hours)
           self.reprname = reprname
           self.stdname = stdname
           self.dstname = dstname

       def __repr__(self):
           return self.reprname

       def tzname(self, dt):
           if self.dst(dt):
               return self.dstname
           else:
               return self.stdname

       def utcoffset(self, dt):
           return self.stdoffset + self.dst(dt)

       def dst(self, dt):
           if dt is None or dt.tzinfo is None:
               # An exception may be sensible here, in one or both cases.
               # It depends on how you want to treat them.  The default
               # fromutc() implementation (called by the default astimezone()
               # implementation) passes a datetime with dt.tzinfo is self.
               return ZERO
           assert dt.tzinfo is self
           start, end = us_dst_range(dt.year)
           # Can't compare naive to aware objects, so strip the timezone from
           # dt first.
           dt = dt.replace(tzinfo=None)
           if start + HOUR <= dt < end - HOUR:
               # DST is in effect.
               return HOUR
           if end - HOUR <= dt < end:
               # Fold (an ambiguous hour): use dt.fold to disambiguate.
               return ZERO if dt.fold else HOUR
           if start <= dt < start + HOUR:
               # Gap (a non-existent hour): reverse the fold rule.
               return HOUR if dt.fold else ZERO
           # DST is off.
           return ZERO

       def fromutc(self, dt):
           assert dt.tzinfo is self
           start, end = us_dst_range(dt.year)
           start = start.replace(tzinfo=self)
           end = end.replace(tzinfo=self)
           std_time = dt + self.stdoffset
           dst_time = std_time + HOUR
           if end <= dst_time < end + HOUR:
               # Repeated hour
               return std_time.replace(fold=1)
           if std_time < start or dst_time >= end:
               # Standard time
               return std_time
           if start <= std_time < end - HOUR:
               # Daylight saving time
               return dst_time


   Eastern  = USTimeZone(-5, "Eastern",  "EST", "EDT")
   Central  = USTimeZone(-6, "Central",  "CST", "CDT")
   Mountain = USTimeZone(-7, "Mountain", "MST", "MDT")
   Pacific  = USTimeZone(-8, "Pacific",  "PST", "PDT")

Note that there are unavoidable subtleties twice per year in a
"tzinfo" subclass accounting for both standard and daylight time, at
the DST transition points.  For concreteness, consider US Eastern (UTC
-0500), where EDT begins the minute after 1:59 (EST) on the second
Sunday in March, and ends the minute after 1:59 (EDT) on the first
Sunday in November:

     UTC   3:MM  4:MM  5:MM  6:MM  7:MM  8:MM
     EST  22:MM 23:MM  0:MM  1:MM  2:MM  3:MM
     EDT  23:MM  0:MM  1:MM  2:MM  3:MM  4:MM

   start  22:MM 23:MM  0:MM  1:MM  3:MM  4:MM

     end  23:MM  0:MM  1:MM  1:MM  2:MM  3:MM

When DST starts (the "start" line), the local wall clock leaps from
1:59 to 3:00.  A wall time of the form 2:MM doesn't really make sense
on that day, so "astimezone(Eastern)" won't deliver a result with
"hour == 2" on the day DST begins.  For example, at the Spring forward
transition of 2016, we get

>>> u0 = datetime(2016, 3, 13, 5, tzinfo=timezone.utc)
>>> for i in range(4):
...     u = u0 + i*HOUR
...     t = u.astimezone(Eastern)
...     print(u.time(), 'UTC =', t.time(), t.tzname())
...
05:00:00 UTC = 00:00:00 EST
06:00:00 UTC = 01:00:00 EST
07:00:00 UTC = 03:00:00 EDT
08:00:00 UTC = 04:00:00 EDT

When DST ends (the "end" line), there's a potentially worse problem:
there's an hour that can't be spelled unambiguously in local wall
time: the last hour of daylight time.  In Eastern, that's times of the
form 5:MM UTC on the day daylight time ends.  The local wall clock
leaps from 1:59 (daylight time) back to 1:00 (standard time) again.
Local times of the form 1:MM are ambiguous. "astimezone()" mimics the
local clock's behavior by mapping two adjacent UTC hours into the same
local hour then.  In the Eastern example, UTC times of the form 5:MM
and 6:MM both map to 1:MM when converted to Eastern, but earlier times
have the "fold" attribute set to 0 and the later times have it set to
1. For example, at the Fall back transition of 2016, we get

>>> u0 = datetime(2016, 11, 6, 4, tzinfo=timezone.utc)
>>> for i in range(4):
...     u = u0 + i*HOUR
...     t = u.astimezone(Eastern)
...     print(u.time(), 'UTC =', t.time(), t.tzname(), t.fold)
...
04:00:00 UTC = 00:00:00 EDT 0
05:00:00 UTC = 01:00:00 EDT 0
06:00:00 UTC = 01:00:00 EST 1
07:00:00 UTC = 02:00:00 EST 0

Note that the "datetime" instances that differ only by the value of
the "fold" attribute are considered equal in comparisons.

Aplicações que não podem suportar horário na parede com ambiguidades
devem explicitamente verificar o valor do atributo "fold" ou evitar o
uso de subclasses "tzinfo" híbridas; não existem ambiguidades ao usar
"timezone", ou qualquer outra subclasse "tzinfo" com diferença fixa
(tal como uma classe representando apenas o horário padrão na costa
leste EST (diferença fixa de -5 horas), ou apenas o horário de verão
na costa leste EDT (diferença fixa de -4 horas)).

Ver também:

  dateutil.tz
     The standard library has "timezone" class for handling arbitrary
     fixed offsets from UTC and "timezone.utc" as UTC timezone
     instance.

     *dateutil.tz* library brings the *IANA timezone database* (also
     known as the Olson database) to Python and its usage is
     recommended.

  Base de dados de fusos horários IANA
     O banco de dados de fuso horário (comumente chando de tz, tzdata
     ou zoneinfo) contém código e dados que representam o histórico de
     hora local para muitas localizações representativas ao redor do
     globo. Ele é atualizado periodicamente para refletir mudanças
     feitas por corpos políticos para limites de fuso horário,
     diferenças UTC, e regras de horário de verão.


8.1.7. Objetos "timezone"
=========================

The "timezone" class is a subclass of "tzinfo", each instance of which
represents a timezone defined by a fixed offset from UTC.  Note that
objects of this class cannot be used to represent timezone information
in the locations where different offsets are used in different days of
the year or where historical changes have been made to civil time.

class datetime.timezone(offset, name=None)

   The *offset* argument must be specified as a "timedelta" object
   representing the difference between the local time and UTC.  It
   must be strictly between "-timedelta(hours=24)" and
   "timedelta(hours=24)" and represent a whole number of minutes,
   otherwise "ValueError" is raised.

   The *name* argument is optional.  If specified it must be a string
   that will be used as the value returned by the "datetime.tzname()"
   method.

   Novo na versão 3.2.

timezone.utcoffset(dt)

   Return the fixed value specified when the "timezone" instance is
   constructed.  The *dt* argument is ignored.  The return value is a
   "timedelta" instance equal to the difference between the local time
   and UTC.

timezone.tzname(dt)

   Return the fixed value specified when the "timezone" instance is
   constructed.  If *name* is not provided in the constructor, the
   name returned by "tzname(dt)" is generated from the value of the
   "offset" as follows.  If *offset* is "timedelta(0)", the name is
   "UTC", otherwise it is a string 'UTC±HH:MM', where ± is the sign of
   "offset", HH and MM are two digits of "offset.hours" and
   "offset.minutes" respectively.

   Alterado na versão 3.6: Name generated from "offset=timedelta(0)"
   is now plain 'UTC', not 'UTC+00:00'.

timezone.dst(dt)

   Sempre retorna "None".

timezone.fromutc(dt)

   Return "dt + offset".  The *dt* argument must be an aware
   "datetime" instance, with "tzinfo" set to "self".

Atributos de classe:

timezone.utc

   O fuso horário UTC, "timezone(timedelta(0))".


8.1.8. Comportamento de "strftime()" e "strptime()"
===================================================

"date", "datetime", and "time" objects all support a
"strftime(format)" method, to create a string representing the time
under the control of an explicit format string.  Broadly speaking,
"d.strftime(fmt)" acts like the "time" module's "time.strftime(fmt,
d.timetuple())" although not all objects support a "timetuple()"
method.

Conversely, the "datetime.strptime()" class method creates a
"datetime" object from a string representing a date and time and a
corresponding format string. "datetime.strptime(date_string, format)"
is equivalent to "datetime(*(time.strptime(date_string,
format)[0:6]))", except when the format includes sub-second components
or timezone offset information, which are supported in
"datetime.strptime" but are discarded by "time.strptime".

For "time" objects, the format codes for year, month, and day should
not be used, as time objects have no such values.  If they're used
anyway, "1900" is substituted for the year, and "1" for the month and
day.

For "date" objects, the format codes for hours, minutes, seconds, and
microseconds should not be used, as "date" objects have no such
values.  If they're used anyway, "0" is substituted for them.

The full set of format codes supported varies across platforms,
because Python calls the platform C library's "strftime()" function,
and platform variations are common.  To see the full set of format
codes supported on your platform, consult the *strftime(3)*
documentation.

The following is a list of all the format codes that the C standard
(1989 version) requires, and these work on all platforms with a
standard C implementation.  Note that the 1999 version of the C
standard added additional format codes.

+-------------+----------------------------------+--------------------------+---------+
| Diretiva    | Significado                      | Exemplo                  | Notas   |
|=============|==================================|==========================|=========|
| "%a"        | Dias da semana como nomes        | Sun, Mon, ..., Sat       | (1)     |
|             | abreviados da localidade.        | (en_US); So, Mo, ..., Sa |         |
|             |                                  | (de_DE)                  |         |
+-------------+----------------------------------+--------------------------+---------+
| "%A"        | Dia da semana como nome completo | Sunday, Monday, ...,     | (1)     |
|             | da localidade.                   | Saturday (en_US);        |         |
|             |                                  | Sonntag, Montag, ...,    |         |
|             |                                  | Samstag (de_DE)          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%w"        | Dia da semana como um número     | 0, 1, ..., 6             |         |
|             | decimal, onde 0 é domingo e 6 é  |                          |         |
|             | sábado.                          |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%d"        | Dia do mês como um número        | 01, 02, ..., 31          |         |
|             | decimal com zeros a esquerda.    |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%b"        | Mês como nome da localidade      | Jan, Feb, ..., Dec       | (1)     |
|             | abreviado.                       | (en_US); Jan, Feb, ...,  |         |
|             |                                  | Dez (de_DE)              |         |
+-------------+----------------------------------+--------------------------+---------+
| "%B"        | Mês como nome completo da        | January, February, ...,  | (1)     |
|             | localidade.                      | December (en_US);        |         |
|             |                                  | janeiro, fevereiro, ..., |         |
|             |                                  | dezembro (pt_BR)         |         |
+-------------+----------------------------------+--------------------------+---------+
| "%m"        | Mês como um número decimal com   | 01, 02, ..., 12          |         |
|             | zeros a esquerda.                |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%y"        | Ano sem século como um número    | 00, 01, ..., 99          |         |
|             | decimal com zeros a esquerda.    |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%Y"        | Ano com o século como um número  | 0001, 0002, ..., 2013,   | (2)     |
|             | decimal.                         | 2014, ..., 9998, 9999    |         |
+-------------+----------------------------------+--------------------------+---------+
| "%H"        | Hora (relógio de 24 horas) como  | 00, 01, ..., 23          |         |
|             | um número decimal com zeros a    |                          |         |
|             | esquerda.                        |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%I"        | Hora (relógio de 12 horas) como  | 01, 02, ..., 12          |         |
|             | um número decimal com zeros a    |                          |         |
|             | esquerda.                        |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%p"        | Equivalente da localidade a AM   | AM, PM (en_US); am, pm   | (1),    |
|             | ou PM.                           | (de_DE)                  | (3)     |
+-------------+----------------------------------+--------------------------+---------+
| "%M"        | Minutos como um número decimal,  | 00, 01, ..., 59          |         |
|             | com zeros a esquerda.            |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%S"        | Segundos como um número decimal, | 00, 01, ..., 59          | (4)     |
|             | com zeros a esquerda.            |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%f"        | Micro-segundos como um número    | 000000, 000001, ...,     | (5)     |
|             | decimal, com zeros a esquerda.   | 999999                   |         |
+-------------+----------------------------------+--------------------------+---------+
| "%z"        | UTC offset in the form +HHMM or  | (empty), +0000, -0400,   | (6)     |
|             | -HHMM (empty string if the       | +1030                    |         |
|             | object is naive).                |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%Z"        | Nome do fuso horário (string     | (empty), UTC, EST, CST   |         |
|             | vazia se o objeto é ingênuo).    |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%j"        | Dia do ano como um número        | 001, 002, ..., 366       |         |
|             | decimal, com zeros a esquerda.   |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%U"        | Número da semana do ano (Domingo | 00, 01, ..., 53          | (7)     |
|             | como o primeiro dia da semana)   |                          |         |
|             | como um número decimal, com      |                          |         |
|             | zeros a esquerda. Todos os dias  |                          |         |
|             | em um ano novo precedendo o      |                          |         |
|             | primeiro domingo são             |                          |         |
|             | considerados como estando na     |                          |         |
|             | semana 0.                        |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%W"        | Número da semana do ano          | 00, 01, ..., 53          | (7)     |
|             | (Segunda-feira como o primeiro   |                          |         |
|             | dia da semana) como um número    |                          |         |
|             | decimal. Todos os dias em um ano |                          |         |
|             | novo precedendo a primeira       |                          |         |
|             | segunda-feira são considerados   |                          |         |
|             | como estando na semana 0.        |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%c"        | Representação de data e hora     | Tue Aug 16 21:30:00 1988 | (1)     |
|             | apropriada da localidade.        | (en_US); Di 16 Aug       |         |
|             |                                  | 21:30:00 1988 (de_DE)    |         |
+-------------+----------------------------------+--------------------------+---------+
| "%x"        | Representação de data apropriada | 08/16/88 (None);         | (1)     |
|             | de localidade.                   | 08/16/1988 (en_US);      |         |
|             |                                  | 16.08.1988 (de_DE)       |         |
+-------------+----------------------------------+--------------------------+---------+
| "%X"        | Representação de hora apropriada | 21:30:00 (en_US);        | (1)     |
|             | da localidade.                   | 21:30:00 (de_DE)         |         |
+-------------+----------------------------------+--------------------------+---------+
| "%%"        | Um caractere literal "'%'".      | %                        |         |
+-------------+----------------------------------+--------------------------+---------+

Several additional directives not required by the C89 standard are
included for convenience. These parameters all correspond to ISO 8601
date values. These may not be available on all platforms when used
with the "strftime()" method. The ISO 8601 year and ISO 8601 week
directives are not interchangeable with the year and week number
directives above. Calling "strptime()" with incomplete or ambiguous
ISO 8601 directives will raise a "ValueError".

+-------------+----------------------------------+--------------------------+---------+
| Diretiva    | Significado                      | Exemplo                  | Notas   |
|=============|==================================|==========================|=========|
| "%G"        | Ano ISO 8601 com o século        | 0001, 0002, ..., 2013,   | (8)     |
|             | representando o ano que a maior  | 2014, ..., 9998, 9999    |         |
|             | parte da semana ISO ("%V").      |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%u"        | Dia de semana ISO 8601 como um   | 1, 2, ..., 7             |         |
|             | número decimal onde 1 é segunda- |                          |         |
|             | feira.                           |                          |         |
+-------------+----------------------------------+--------------------------+---------+
| "%V"        | Semana ISO 8601 como um número   | 01, 02, ..., 53          | (8)     |
|             | decimal, com segunda-feira como  |                          |         |
|             | o primeiro dia da semana. A      |                          |         |
|             | semana 01 é a semana contendo o  |                          |         |
|             | dia 4 de Janeiro.                |                          |         |
+-------------+----------------------------------+--------------------------+---------+

Novo na versão 3.6: "%G", "%u" e "%V" foram adicionados.

Notas:

1. Devido ao fato que o formato depende da localidade atual, deve-se
   tomar cuidado ao fazer suposições sobre o valor na saída.
   Ordenamento de campos irá variar (por exemplo, "mês/dia/ano" versus
   "dia/mês/ano"), e a saída pode conter caracteres Unicode que foram
   codificados usando a codificação padrão da localidade (por exemplo,
   se a localidade atual é "ja_JP", a codificação padrão pode ser
   qualquer uma dentre "eucJP", "SJIS", ou "utf-8"; utilize
   "locale.getlocale()" para determinar a codificação atual da
   localidade).

2. O método "strptime()" pode interpretar anos no intervalo [1, 9999],
   mas anos < 1000 devem ser preenchidos com 0 para ter 4 dígitos de
   extensão.

   Alterado na versão 3.2: Em versões anteriores, o método
   "strftime()" era restrito a anos>= 1900.

   Alterado na versão 3.3: Na versão 3.2, o método "strftime()" era
   restrito a anos >= 1000.

3. Quando usado com o método "strptime()", a diretiva "%p" apenas
   afeta as horas na saída se a diretiva "%I" é usada para analisar a
   hora.

4. Ao contrário do módulo "time", o módulo "datetime" não suporta
   segundos bissextos.

5. When used with the "strptime()" method, the "%f" directive accepts
   from one to six digits and zero pads on the right.  "%f" is an
   extension to the set of format characters in the C standard (but
   implemented separately in datetime objects, and therefore always
   available).

6. Para um objeto ingênuo, os códigos de formatação "%z" e "%Z" são
   substituídos por strings vazias.

   Para um objeto consciente:

   "%z"
      "utcoffset()" is transformed into a 5-character string of the
      form +HHMM or -HHMM, where HH is a 2-digit string giving the
      number of UTC offset hours, and MM is a 2-digit string giving
      the number of UTC offset minutes.  For example, if "utcoffset()"
      returns "timedelta(hours=-3, minutes=-30)", "%z" is replaced
      with the string "'-0330'".

   "%Z"
      If "tzname()" returns "None", "%Z" is replaced by an empty
      string.  Otherwise "%Z" is replaced by the returned value, which
      must be a string.

   Alterado na versão 3.2: When the "%z" directive is provided to the
   "strptime()" method, an aware "datetime" object will be produced.
   The "tzinfo" of the result will be set to a "timezone" instance.

7. Quando for usado com o método "strptime()", "%U" e "%W" são apenas
   usados em cálculos quando o dia da semana e o ano do calendário
   ("%Y") são especificados.

8. Similar a "%U" e "%W", "%V" é apenas usado em cálculos quando o dia
   da semana e o ano ISO ("%G") são especificados em uma string de
   formatação "strptime()". Perceba também que "%G" e "%Y" não são
   intercambiáveis.

-[ Notas de rodapé ]-

[1] Se, isto é, nós ignoramos os efeitos da Relatividade
