builtins
— 内容对象
¶
This module provides direct access to all ‘built-in’ identifiers of Python; for example,
builtins.open
is the full name for the built-in function
open()
。见
内置函数
and
内置常量
for documentation.
This module is not normally accessed explicitly by most applications, but can be useful in modules that provide objects with the same name as a built-in value, but in which the built-in of that name is also needed. For example, in a module that wants to implement an
open()
function that wraps the built-in
open()
, this module can be used directly:
import builtins
def open(path):
f = builtins.open(path, 'r')
return UpperCaser(f)
class UpperCaser:
'''Wrapper around a file that converts output to upper-case.'''
def __init__(self, f):
self._f = f
def read(self, count=-1):
return self._f.read(count).upper()
# ...
As an implementation detail, most modules have the name
__builtins__
made available as part of their globals. The value of
__builtins__
is normally either this module or the value of this module’s
__dict__
attribute. Since this is an implementation detail, it may not be used by alternate implementations of Python.