python - how to get a defautdict(set) like this form : {str : { str : int } } -

i got dictionary this

{('a','b'):3, ('b','c'): 2, ('a','c'): 5} 

i want convert form :

{'b': {'c': 2}, 'a': {'c': 5, 'b': 3}}   

that means have build dictionary form:

   d:{(str1,str2):int}   -->     {str1 : { str2 : int } } 

you not want defaultdict based on set based on dict instead.

dic = {('a','b'):3, ('b','c'): 2, ('a','c'): 5} dic2 = defaultdict(dict) j,k in dic:     dic2[j][k] = dic[(j,k)] ## dic2 = defaultdict(<type 'dict'>, {'a': {'c': 5, 'b': 3}, 'b': {'c': 2}}) 

on side note, d.keys() iterable, there no need call list(d.keys()). in fact, iterate on keys of dictionary d, best call for key in d: