目的
获得一个首尾不含多余空格的字符串
方法
可以使用字符串的以下方法处理：
string.lstrip(s[, chars])
Return a copy of the string with leading characters removed. If chars is omitted or None, whitespace characters are removed. If given and not None, chars must be a string; the characters in the string will be stripped from the beginning of the string this method is called on.
string.rstrip(s[, chars])
Return a copy of the string with trailing characters removed. If chars is omitted or None, whitespace characters are removed. If given and not None, chars must be a string; the characters in the string will be stripped from the end of the string this method is called on.
string.strip(s[, chars])
Return a copy of the string with leading and trailing characters removed. If chars is omitted or None, whitespace characters are removed. If given and not None, chars must be a string; the characters in the string will be stripped from the both ends of the string this method is called on.
具体的效果如下：
In [10]: x=' Hi,Jack! '
In [11]: print '|',x.lstrip(),'|',x.rstrip(),'|',x.strip(),'|'
| Hi,Jack! | Hi,Jack! | Hi,Jack! |
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其中提供的参数chars用来删除特定的符号，注意空格并没有被移除，例如：
In [12]: x='yxyxyxxxyy Hello xyxyxyy'
In [13]: print x.strip('xy')
Hello
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