python join的用法

#字符串

>>> a="abcd"

>>> ",".join(a)

'a,b,c,d'

#列表

>>> "|".join(['a','b','c'])

'a|b|c'

#元祖

>>> ",".join(('a','b','c'))

'a,b,c'

#字典

>>> ",".join({'a':1,'b':2,'c':3})
'a,c,b'