Python Pre-loads a batch of built-in modules into memory when it initializes the runtime environment.
All pre-loaded modules are as follows:
1>>> forIteminchSys.modules.items ():2...PrintItem3 ...4('Copy_reg', <module'Copy_reg' from '/users/kris/git_space/pyv/lib/python2.7/copy_reg.pyc'>)5('Encodings', <module'Encodings' from '/users/kris/git_space/pyv/lib/python2.7/encodings/__init__.pyc'>)6('site', <module'site' from '/users/kris/git_space/pyv/lib/python2.7/site.pyc'>)7('__builtin__', <module'__builtin__'(built-inch) >)8('__main__', <module'__main__'(built-inch) >)9('encodings.encodings', None)Ten('ABC', <module'ABC' from '/users/kris/git_space/pyv/lib/python2.7/abc.pyc'>) One('Posixpath', <module'Posixpath' from '/users/kris/git_space/pyv/lib/python2.7/posixpath.pyc'>) A('_weakrefset', <module'_weakrefset' from '/users/kris/git_space/pyv/lib/python2.7/_weakrefset.pyc'>) -('errno', <module'errno'(built-inch) >) -('Encodings.codecs', None) the('_abcoll', <module'_abcoll' from '/users/kris/git_space/pyv/lib/python2.7/_abcoll.pyc'>) -('Types', <module'Types' from '/users/kris/git_space/pyv/lib/python2.7/types.pyc'>) -('_codecs', <module'_codecs'(built-inch) >) -('_warnings', <module'_warnings'(built-inch) >) +('Genericpath', <module'Genericpath' from '/users/kris/git_space/pyv/lib/python2.7/genericpath.pyc'>) -('Stat', <module'Stat' from '/users/kris/git_space/pyv/lib/python2.7/stat.pyc'>) +('Zipimport', <module'Zipimport'(built-inch) >) A('encodings.__builtin__', None) at('Warnings', <module'Warnings' from '/users/kris/git_space/pyv/lib/python2.7/warnings.pyc'>) -('userdict', <module'userdict' from '/users/kris/git_space/pyv/lib/python2.7/userdict.pyc'>) -('Encodings.utf_8', <module'Encodings.utf_8' from '/users/kris/git_space/pyv/lib/python2.7/encodings/utf_8.pyc'>) -('SYS', <module'SYS'(built-inch) >) -('Codecs', <module'Codecs' from '/users/kris/git_space/pyv/lib/python2.7/codecs.pyc'>) -('ReadLine', <module'ReadLine' from '/users/kris/git_space/pyv/lib/python2.7/lib-dynload/readline.so'>) in('Os.path', <module'Posixpath' from '/users/kris/git_space/pyv/lib/python2.7/posixpath.pyc'>) -('Signal', <module'Signal'(built-inch) >) to('Linecache', <module'Linecache' from '/users/kris/git_space/pyv/lib/python2.7/linecache.pyc'>) +('POSIX', <module'POSIX'(built-inch) >) -('encodings.aliases', <module'encodings.aliases' from '/users/kris/git_space/pyv/lib/python2.7/encodings/aliases.pyc'>) the('Exceptions', <module'Exceptions'(built-inch) >) *('OS', <module'OS' from '/users/kris/git_space/pyv/lib/python2.7/os.pyc'>) $('_weakref', <module'_weakref'(built-inch) >)
Python all pre-loaded modules when initializing the runtime environment