[Python] How to sum values across dicts? [duplicate]

I'm using python 3.7. I have a list of dicts that and I want to create a concatenated dict where that concatenated dicts sums over values (grouped by keys) per key in the initial list of dicts.

So e.g.,

d1 = {1: 1.1, 2: 2.2}
d2 = {1: 3.3, 4: 5.5}


The result should be:

final_dict = {1: 4.4, 2: 2.2, 4: 5.5}


I tried to do dict([*d1.items(), *d2.items()]) but this overwrites duplicate keys instead of summing them.

Currently, I just do

def _sum_dicts_by_key(dicts):
result = defaultdict(float)
for d in dicts:
for k, v in d.items():
result[k] += v


but I feel there should be a pythonic way to do it without explicitly looping?

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