Objetos diccionario
*******************

type PyDictObject

   Este subtipo de "PyObject" representa un objeto diccionario de
   Python.

PyTypeObject PyDict_Type
    * Part of the Stable ABI.*

   Esta instancia de "PyTypeObject" representa el tipo diccionario de
   Python. Este es el mismo objeto que "dict" en la capa de Python.

int PyDict_Check(PyObject *p)

   Retorna verdadero si *p* es un objeto "dict" o una instancia de un
   subtipo del tipo "dict". Esta función siempre finaliza con éxito.

int PyDict_CheckExact(PyObject *p)

   Retorna verdadero si *p* es un objeto "dict", pero no una instancia
   de un subtipo del tipo "dict". Esta función siempre finaliza con
   éxito.

PyObject *PyDict_New()
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un nuevo diccionario vacío, o "NULL" en caso de falla.

PyObject *PyDictProxy_New(PyObject *mapping)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un objeto a "types.MappingProxyType" para una asignación
   que imponga un comportamiento de solo lectura. Esto normalmente se
   usa para crear una vista para evitar la modificación del
   diccionario para los tipos de clase no dinámicos.

void PyDict_Clear(PyObject *p)
    * Part of the Stable ABI.*

   Vacía un diccionario existente de todos los pares clave-valor
   (*key-value*).

int PyDict_Contains(PyObject *p, PyObject *key)
    * Part of the Stable ABI.*

   Determine si el diccionario *p* contiene *key*. Si un elemento en
   *p* coincide con la clave *key*, retorna "1"; de lo contrario,
   retorna "0". En caso de error, retorna "-1". Esto es equivalente a
   la expresión de Python "key in p".

int PyDict_ContainsString(PyObject *p, const char *key)

   This is the same as "PyDict_Contains()", but *key* is specified as
   a const char* UTF-8 encoded bytes string, rather than a PyObject*.

   Added in version 3.13.

PyObject *PyDict_Copy(PyObject *p)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un nuevo diccionario que contiene los mismos pares clave-
   valor (*key-value*) que *p*.

int PyDict_SetItem(PyObject *p, PyObject *key, PyObject *val)
    * Part of the Stable ABI.*

   Inserta *val* en el diccionario *p* con una clave *key*. *key* debe
   ser *hashable*; si no lo es, se lanzará "TypeError". Retorna "0" en
   caso de éxito o "-1" en caso de error. Esta función *no* roba una
   referencia a *val*.

int PyDict_SetItemString(PyObject *p, const char *key, PyObject *val)
    * Part of the Stable ABI.*

   This is the same as "PyDict_SetItem()", but *key* is specified as a
   const char* UTF-8 encoded bytes string, rather than a PyObject*.

int PyDict_DelItem(PyObject *p, PyObject *key)
    * Part of the Stable ABI.*

   Remove the entry in dictionary *p* with key *key*. *key* must be
   *hashable*; if it isn't, "TypeError" is raised. If *key* is not in
   the dictionary, "KeyError" is raised. Return "0" on success or "-1"
   on failure.

int PyDict_DelItemString(PyObject *p, const char *key)
    * Part of the Stable ABI.*

   This is the same as "PyDict_DelItem()", but *key* is specified as a
   const char* UTF-8 encoded bytes string, rather than a PyObject*.

int PyDict_GetItemRef(PyObject *p, PyObject *key, PyObject **result)
    * Part of the Stable ABI since version 3.13.*

   Return a new *strong reference* to the object from dictionary *p*
   which has a key *key*:

   * If the key is present, set **result* to a new *strong reference*
     to the value and return "1".

   * If the key is missing, set **result* to "NULL" and return "0".

   * On error, raise an exception and return "-1".

   Added in version 3.13.

   See also the "PyObject_GetItem()" function.

PyObject *PyDict_GetItem(PyObject *p, PyObject *key)
    *Return value: Borrowed reference.** Part of the Stable ABI.*

   Return a *borrowed reference* to the object from dictionary *p*
   which has a key *key*.  Return "NULL" if the key *key* is missing
   *without* setting an exception.

   Nota:

     Exceptions that occur while this calls "__hash__()" and
     "__eq__()" methods are silently ignored. Prefer the
     "PyDict_GetItemWithError()" function instead.

   Distinto en la versión 3.10: Calling this API without an *attached
   thread state* had been allowed for historical reason. It is no
   longer allowed.

PyObject *PyDict_GetItemWithError(PyObject *p, PyObject *key)
    *Return value: Borrowed reference.** Part of the Stable ABI.*

   Variante de "PyDict_GetItem()" que no suprime las excepciones.
   Retorna "NULL" **con** una excepción establecida si se produjo una
   excepción. Retorna "NULL" **sin** una excepción establecida si la
   clave no estaba presente.

PyObject *PyDict_GetItemString(PyObject *p, const char *key)
    *Return value: Borrowed reference.** Part of the Stable ABI.*

   This is the same as "PyDict_GetItem()", but *key* is specified as a
   const char* UTF-8 encoded bytes string, rather than a PyObject*.

   Nota:

     Exceptions that occur while this calls "__hash__()" and
     "__eq__()" methods or while creating the temporary "str" object
     are silently ignored. Prefer using the
     "PyDict_GetItemWithError()" function with your own
     "PyUnicode_FromString()" *key* instead.

int PyDict_GetItemStringRef(PyObject *p, const char *key, PyObject **result)
    * Part of the Stable ABI since version 3.13.*

   Similar to "PyDict_GetItemRef()", but *key* is specified as a const
   char* UTF-8 encoded bytes string, rather than a PyObject*.

   Added in version 3.13.

PyObject *PyDict_SetDefault(PyObject *p, PyObject *key, PyObject *defaultobj)
    *Return value: Borrowed reference.*

   Esto es lo mismo al nivel de Python "dict.setdefault()". Si está
   presente, retorna el valor correspondiente a *key* del diccionario
   *p*. Si la clave no está en el "dict", se inserta con el valor
   *defaultobj* y se retorna *defaultobj*. Esta función evalúa la
   función *hash* de *key* solo una vez, en lugar de evaluarla
   independientemente para la búsqueda y la inserción.

   Added in version 3.4.

int PyDict_SetDefaultRef(PyObject *p, PyObject *key, PyObject *default_value, PyObject **result)

   Inserts *default_value* into the dictionary *p* with a key of *key*
   if the key is not already present in the dictionary. If *result* is
   not "NULL", then **result* is set to a *strong reference* to either
   *default_value*, if the key was not present, or the existing value,
   if *key* was already present in the dictionary. Returns "1" if the
   key was present and *default_value* was not inserted, or "0" if the
   key was not present and *default_value* was inserted. On failure,
   returns "-1", sets an exception, and sets "*result" to "NULL".

   For clarity: if you have a strong reference to *default_value*
   before calling this function, then after it returns, you hold a
   strong reference to both *default_value* and **result* (if it's not
   "NULL"). These may refer to the same object: in that case you hold
   two separate references to it.

   Added in version 3.13.

int PyDict_Pop(PyObject *p, PyObject *key, PyObject **result)

   Remove *key* from dictionary *p* and optionally return the removed
   value. Do not raise "KeyError" if the key missing.

   * If the key is present, set **result* to a new reference to the
     removed value if *result* is not "NULL", and return "1".

   * If the key is missing, set **result* to "NULL" if *result* is not
     "NULL", and return "0".

   * On error, raise an exception and return "-1".

   Similar to "dict.pop()", but without the default value and not
   raising "KeyError" if the key missing.

   Added in version 3.13.

int PyDict_PopString(PyObject *p, const char *key, PyObject **result)

   Similar to "PyDict_Pop()", but *key* is specified as a const char*
   UTF-8 encoded bytes string, rather than a PyObject*.

   Added in version 3.13.

PyObject *PyDict_Items(PyObject *p)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un "PyListObject" que contiene todos los elementos del
   diccionario.

PyObject *PyDict_Keys(PyObject *p)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un "PyListObject" que contiene todas las claves del
   diccionario.

PyObject *PyDict_Values(PyObject *p)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un "PyListObject" que contiene todos los valores del
   diccionario *p*.

Py_ssize_t PyDict_Size(PyObject *p)
    * Part of the Stable ABI.*

   Retorna el número de elementos en el diccionario. Esto es
   equivalente a "len(p)" en un diccionario.

int PyDict_Next(PyObject *p, Py_ssize_t *ppos, PyObject **pkey, PyObject **pvalue)
    * Part of the Stable ABI.*

   Iterate over all key-value pairs in the dictionary *p*.  The
   "Py_ssize_t" referred to by *ppos* must be initialized to "0" prior
   to the first call to this function to start the iteration; the
   function returns true for each pair in the dictionary, and false
   once all pairs have been reported.  The parameters *pkey* and
   *pvalue* should either point to PyObject* variables that will be
   filled in with each key and value, respectively, or may be "NULL".
   Any references returned through them are borrowed.  *ppos* should
   not be altered during iteration. Its value represents offsets
   within the internal dictionary structure, and since the structure
   is sparse, the offsets are not consecutive.

   Por ejemplo:

      PyObject *key, *value;
      Py_ssize_t pos = 0;

      while (PyDict_Next(self->dict, &pos, &key, &value)) {
          /* do something interesting with the values... */
          ...
      }

   El diccionario *p* no debe mutarse durante la iteración. Es seguro
   modificar los valores de las claves a medida que recorre el
   diccionario, pero solo mientras el conjunto de claves no cambie.
   Por ejemplo:

      PyObject *key, *value;
      Py_ssize_t pos = 0;

      while (PyDict_Next(self->dict, &pos, &key, &value)) {
          long i = PyLong_AsLong(value);
          if (i == -1 && PyErr_Occurred()) {
              return -1;
          }
          PyObject *o = PyLong_FromLong(i + 1);
          if (o == NULL)
              return -1;
          if (PyDict_SetItem(self->dict, key, o) < 0) {
              Py_DECREF(o);
              return -1;
          }
          Py_DECREF(o);
      }

   The function is not thread-safe in the *free-threaded* build
   without external synchronization.  You can use
   "Py_BEGIN_CRITICAL_SECTION" to lock the dictionary while iterating
   over it:

      Py_BEGIN_CRITICAL_SECTION(self->dict);
      while (PyDict_Next(self->dict, &pos, &key, &value)) {
          ...
      }
      Py_END_CRITICAL_SECTION();

   Nota:

     On the free-threaded build, this function can be used safely
     inside a critical section. However, the references returned for
     *pkey* and *pvalue* are *borrowed* and are only valid while the
     critical section is held. If you need to use these objects
     outside the critical section or when the critical section can be
     suspended, create a *strong reference* (for example, using
     "Py_NewRef()").

int PyDict_Merge(PyObject *a, PyObject *b, int override)
    * Part of the Stable ABI.*

   Itera sobre el objeto de mapeo *b* agregando pares clave-valor al
   diccionario *a*. *b* puede ser un diccionario o cualquier objeto
   que soporte "PyMapping_Keys()" y "PyObject_GetItem()". Si
   *override* es verdadero, los pares existentes en *a* se
   reemplazarán si se encuentra una clave coincidente en *b*, de lo
   contrario, los pares solo se agregarán si no hay una clave
   coincidente en *a*. Retorna "0" en caso de éxito o "-1" si se lanza
   una excepción.

int PyDict_Update(PyObject *a, PyObject *b)
    * Part of the Stable ABI.*

   Esto es lo mismo que "PyDict_Merge(a, b, 1)" en C, y es similar a
   "a.update(b)" en Python excepto que "PyDict_Update()" no vuelve a
   la iteración sobre una secuencia de pares de valores clave si el
   segundo argumento no tiene el atributo "claves". Retorna "0" en
   caso de éxito o "-1" si se produjo una excepción.

int PyDict_MergeFromSeq2(PyObject *a, PyObject *seq2, int override)
    * Part of the Stable ABI.*

   Actualiza o combina en el diccionario *a*, desde los pares clave-
   valor en *seq2*. *seq2* debe ser un objeto iterable que produzca
   objetos iterables de longitud 2, vistos como pares clave-valor. En
   el caso de claves duplicadas, el último gana si *override* es
   verdadero, de lo contrario, el primero gana. Retorna "0" en caso de
   éxito o "-1" si se produjo una excepción. El equivalente en Python
   (excepto el valor de retorno)

      def PyDict_MergeFromSeq2(a, seq2, override):
          for key, value in seq2:
              if override or key not in a:
                  a[key] = value

int PyDict_AddWatcher(PyDict_WatchCallback callback)

   Register *callback* as a dictionary watcher. Return a non-negative
   integer id which must be passed to future calls to
   "PyDict_Watch()". In case of error (e.g. no more watcher IDs
   available), return "-1" and set an exception.

   Added in version 3.12.

int PyDict_ClearWatcher(int watcher_id)

   Clear watcher identified by *watcher_id* previously returned from
   "PyDict_AddWatcher()". Return "0" on success, "-1" on error (e.g.
   if the given *watcher_id* was never registered.)

   Added in version 3.12.

int PyDict_Watch(int watcher_id, PyObject *dict)

   Mark dictionary *dict* as watched. The callback granted
   *watcher_id* by "PyDict_AddWatcher()" will be called when *dict* is
   modified or deallocated. Return "0" on success or "-1" on error.

   Added in version 3.12.

int PyDict_Unwatch(int watcher_id, PyObject *dict)

   Mark dictionary *dict* as no longer watched. The callback granted
   *watcher_id* by "PyDict_AddWatcher()" will no longer be called when
   *dict* is modified or deallocated. The dict must previously have
   been watched by this watcher. Return "0" on success or "-1" on
   error.

   Added in version 3.12.

type PyDict_WatchEvent

   Enumeration of possible dictionary watcher events:
   "PyDict_EVENT_ADDED", "PyDict_EVENT_MODIFIED",
   "PyDict_EVENT_DELETED", "PyDict_EVENT_CLONED",
   "PyDict_EVENT_CLEARED", or "PyDict_EVENT_DEALLOCATED".

   Added in version 3.12.

typedef int (*PyDict_WatchCallback)(PyDict_WatchEvent event, PyObject *dict, PyObject *key, PyObject *new_value)

   Type of a dict watcher callback function.

   If *event* is "PyDict_EVENT_CLEARED" or "PyDict_EVENT_DEALLOCATED",
   both *key* and *new_value* will be "NULL". If *event* is
   "PyDict_EVENT_ADDED" or "PyDict_EVENT_MODIFIED", *new_value* will
   be the new value for *key*. If *event* is "PyDict_EVENT_DELETED",
   *key* is being deleted from the dictionary and *new_value* will be
   "NULL".

   "PyDict_EVENT_CLONED" occurs when *dict* was previously empty and
   another dict is merged into it. To maintain efficiency of this
   operation, per-key "PyDict_EVENT_ADDED" events are not issued in
   this case; instead a single "PyDict_EVENT_CLONED" is issued, and
   *key* will be the source dictionary.

   The callback may inspect but must not modify *dict*; doing so could
   have unpredictable effects, including infinite recursion. Do not
   trigger Python code execution in the callback, as it could modify
   the dict as a side effect.

   If *event* is "PyDict_EVENT_DEALLOCATED", taking a new reference in
   the callback to the about-to-be-destroyed dictionary will resurrect
   it and prevent it from being freed at this time. When the
   resurrected object is destroyed later, any watcher callbacks active
   at that time will be called again.

   Callbacks occur before the notified modification to *dict* takes
   place, so the prior state of *dict* can be inspected.

   If the callback sets an exception, it must return "-1"; this
   exception will be printed as an unraisable exception using
   "PyErr_WriteUnraisable()". Otherwise it should return "0".

   There may already be a pending exception set on entry to the
   callback. In this case, the callback should return "0" with the
   same exception still set. This means the callback may not call any
   other API that can set an exception unless it saves and clears the
   exception state first, and restores it before returning.

   Added in version 3.12.
