Python字符串常见操作
(1)find
(2)index
(3)count
(4)replace
(5)split
(6)capitalize
(7)title
(8)startswith
(9)endswith
(10)lower
(11)upper
(12)ljust (left)
(13)rjust
(14)center
(15)lstrip
(16)rstrip
(17)strip
(18)partition
(19)splitlines
(20)isalpha
(21)isdigit
(22)isalnum
(23)isspace
(24)join
(25)切片
--切片