def merge_dicts(d1: dict, d2: dict):
	"""Merge dicts of dictionaries.
	>>> merge_dicts(
		{'name1': {'age': 20}, 'name2': {'age': 30}},
		{'name1': {'phone': '+xxx'}, 'name2': {'phone': '+yyy'}, 'name3': {'phone': '+zzz'}}
	)
	... {'name1': {'age': 20, 'phone': '+xxx'}, 'name2': {'age': 30, 'phone': '+yyy'}}
	"""
	return {k:{**v, **d2.get(k, {})} for k, v in d1.items()}