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
11:func:`open`.  See :ref:`built-in-funcs` and :ref:`built-in-consts` for
12documentation.
13
14
15This module is not normally accessed explicitly by most applications, but can be
16useful in modules that provide objects with the same name as a built-in value,
17but in which the built-in of that name is also needed.  For example, in a module
18that wants to implement an :func:`open` function that wraps the built-in
19:func:`open`, this module can be used directly::
20
21   import builtins
22
23   def open(path):
24       f = builtins.open(path, 'r')
25       return UpperCaser(f)
26
27   class UpperCaser:
28       '''Wrapper around a file that converts output to upper-case.'''
29
30       def __init__(self, f):
31           self._f = f
32
33       def read(self, count=-1):
34           return self._f.read(count).upper()
35
36       # ...
37
38As an implementation detail, most modules have the name ``__builtins__`` made
39available as part of their globals.  The value of ``__builtins__`` is normally
40either this module or the value of this module's :attr:`~object.__dict__` attribute.
41Since this is an implementation detail, it may not be used by alternate
42implementations of Python.
43