Standard Library Modules
Standard library modules are always available but must be imported to be used in client modules. To access them, use one of these formats:
import module
, and fetch attribute names (module.name
)from module import name
, and use module names unqualified (name
)from module import *
, and use module names unqualified (name
)
For instance, to use name argv
in the sys
module, either use
import sys
and name sys.argv
, or use from
sys import argv
and name argv
.
There are many standard library modules; the following sections are not necessarily exhaustive, and aim to document only commonly used names in commonly used modules. See Pythonâs Library Reference for a more complete reference to standard library modules.
In all of the following module sections:
Listed export names followed by parentheses are functions that must be called; others are simple attributes (i.e., variable names in modules).
Module contents document the modulesâ state Python 3.0; see Python manuals for information on attributes unique to version 2 or 3.
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