# 3.5 operator -- Standard operators as functions.

The operator module exports a set of functions implemented in C corresponding to the intrinsic operators of Python. For example, operator.add(x, y) is equivalent to the expression x+y. The function names are those used for special class methods; variants without leading and trailing "__" are also provided for convenience.

The operator module defines the following functions:

Return a + b, for a and b numbers.

sub (a, b)
__sub__ (a, b)
Return a - b.

mul (a, b)
__mul__ (a, b)
Return a * b, for a and b numbers.

div (a, b)
__div__ (a, b)
Return a / b.

mod (a, b)
__mod__ (a, b)
Return a % b.

neg (o)
__neg__ (o)
Return o negated.

pos (o)
__pos__ (o)
Return o positive.

abs (o)
__abs__ (o)
Return the absolute value of o.

inv (o)
__inv__ (o)
Return the inverse of o.

lshift (a, b)
__lshift__ (a, b)
Return a shifted left by b.

rshift (a, b)
__rshift__ (a, b)
Return a shifted right by b.

and_ (a, b)
__and__ (a, b)
Return the bitwise and of a and b.

or_ (a, b)
__or__ (a, b)
Return the bitwise or of a and b.

xor (a, b)
__xor__ (a, b)
Return the bitwise exclusive or of a and b.

not_ (o)
__not__ (o)
Return the outcome of not o.

truth (o)
Return 1 if o is true, and 0 otherwise.

concat (a, b)
__concat__ (a, b)
Return a + b for a and b sequences.

repeat (a, b)
__repeat__ (a, b)
Return a * b where a is a sequence and b is an integer.

contains (a, b)
sequenceIncludes (a, b)
Return the outcome of the test b in a. Note the reversed operands.

countOf (a, b)
Return the number of occurrences of b in a.

indexOf (a, b)
Return the index of the first of occurrence of b in a.

getitem (a, b)
__getitem__ (a, b)
Return the value of a at index b.

setitem (a, b, c)
__setitem__ (a, b, c)
Set the value of a at index b to c.

delitem (a, b)
__delitem__ (a, b)
Remove the value of a at index b.

getslice (a, b, c)
__getslice__ (a, b, c)
Return the slice of a from index b to index c-1.

setslice (a, b, c, v)
__setslice__ (a, b, c, v)
Set the slice of a from index b to index c-1 to the sequence v.

delslice (a, b, c)
__delslice__ (a, b, c)
Delete the slice of a from index b to index c-1.

Example: Build a dictionary that maps the ordinals from 0 to 256 to their character equivalents.

```>>> import operator
>>> d = {}
>>> keys = range(256)
>>> vals = map(chr, keys)
>>> map(operator.setitem, [d]*len(keys), keys, vals)
```

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