python字符串

>>> a=1992
>>> b="free"
>>> print b+ `a`
free1992
>>> print b+str(a)
free1992
>>> print b+repr(a)
free1992
>>>
>>> dos="c:\\news"
>>> print dos
c:\news
>>> dos=r"c:\news"
>>> print dos
c:\news
>>> lang="study Python"
>>> lang[0]
's'
>>> lang[1]
't'
>>> "study Python"[0]
's'
>>>