python - Add dictionary values where keys match -


i have list of dictionaries following:

a=[{'a':1},{'b':2},{'c':3},{'a':-2},{'b':4}]

i need loop through list , add values keys match. result should this:

a=[{'a':-1},{'b':6},{'c':3}]

help doing appreciated.

i able implement like

a = [{'a':1},{'b':2},{'c':3},{'a':-2},{'b':4}] b = {}  x in a:     k,v = x.popitem()      # check if key in our output dict     if k in b.keys():         b[k] += v      # if not, create     else:         b[k] = v

which outputs

b = {'a': -1, 'b': 6, 'c': 3}

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