另一种写法是
res = dict((k,v) for k,v in kwargs.iteritems() if v is not None)
在Python3中,这变成
res = {k:v for k,v in kwargs.items() if v is not None}
另一种写法是
res = dict((k,v) for k,v in kwargs.iteritems() if v is not None)
在Python3中,这变成
res = {k:v for k,v in kwargs.items() if v is not None}