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1:mod:`!builtins` --- Built-in objects
2=====================================
3
4.. module:: builtins
5   :synopsis: The module that provides the built-in namespace.
6
7--------------
8
9This module provides direct access to all 'built-in' identifiers of Python; for
10example, ``builtins.open`` is the full name for the built-in function :func:`open`.
11
12This module is not normally accessed explicitly by most applications, but can be
13useful in modules that provide objects with the same name as a built-in value,
14but in which the built-in of that name is also needed.  For example, in a module
15that wants to implement an :func:`open` function that wraps the built-in
16:func:`open`, this module can be used directly::
17
18   import builtins
19
20   def open(path):
21       f = builtins.open(path, 'r')
22       return UpperCaser(f)
23
24   class UpperCaser:
25       '''Wrapper around a file that converts output to uppercase.'''
26
27       def __init__(self, f):
28           self._f = f
29
30       def read(self, count=-1):
31           return self._f.read(count).upper()
32
33       # ...
34
35As an implementation detail, most modules have the name ``__builtins__`` made
36available as part of their globals.  The value of ``__builtins__`` is normally
37either this module or the value of this module's :attr:`~object.__dict__` attribute.
38Since this is an implementation detail, it may not be used by alternate
39implementations of Python.
40
41.. seealso::
42
43   * :ref:`built-in-consts`
44   * :ref:`bltin-exceptions`
45   * :ref:`built-in-funcs`
46   * :ref:`bltin-types`
47