去除字符串两端的空格和字符

# -*- coding: utf-8 -*-
"""
去除字符串两端的空格和字符
lstrip（）、rstrip（）、strip（）
返回字符串的拷贝
"""
x = '   aaa   '

print '|',x.lstrip(),'|',x.rstrip(),'|',x.strip(),'|'
# Output: | aaa    |    aaa | aaa |

x = 'xyxxyy hejyx yyx'
print '|'+ x.strip('xy')+'|'
# Output：| hejyx |

x = 'yxyxyxyxyxyx   yyxyxyxyx'
print x.lstrip('xy')
# Output：   yyxyxyxyx

print x.rstrip('xy')
# Output: yxyxyxyxyxyx

x = 'xyyyyyxyxyxyxx'
print x.lstrip('xy')
# Output：为空

print x.rstrip('xy')
# Output：为空