如果您经常这样做，则需要构建反向字典：
>>> rev_ref = dict((v,k) for k,v in ref.iteritems())
>>> rev_ref
{'def': 'abc'}
>>> def revmapper(to):
... return rev_ref[to]
如果它很少见，并且您不关心它的效率低下，请执行以下操作：
>>> def revmapper(to):
... for k,v in ref.iteritems():
... if v == to: return k
602392714
清零编程群