c – 4 – dir

dir():
        1 显示函数库中的所有函数名
        2 def dir(object):
        3 dir([object]) -> list of strings
        4 $Exp:
            $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
            $  s=dir(str)
            $  print(s)
            $  #-----------------------------------
            $  ['__add__', ..., 'count', 'encode',
            $  'index', 'isalnum', 'split',... ]
            $  #-----------------------------------
            $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$