I have two lists of python dictionnaries :

l1 = [{"id":1, "name":"A"}, {"id":2, "name":"B"}]
l2 = [{"id":1, "full_name":"Alfred"}, {"id":2, "full_name":"Barbara"}]

My goal is to have a list as follow :

l3 = [{"id":1, "full_name":"Alfred", "name":"A"}, {"id":2, "full_name":"Barbara", "name":"B"}]

I think I could use nested loops to do this, but I'm sure it should be possible to do it in a better and more pythonic way.

from collections import defaultdictres = defaultdict(dict)
for a, b in zip(l1, l2):key1 = a['id']key2 = b['id']res[key1].update(a)res[key2].update(b)print(list(res.values())) # [{'id': 1, 'name': 'A', 'full_name': 'Alfred'}, {'id': 2, 'name': 'B', 'full_name': 'Barbara'}]

Although this would work in a single iteration you might want to simplify your underlying data structures a bit to make them easier to work with.