python update合并字典的方法

>>> for_adoption = {"dogs": 10, "cats": 7, "pythons": 3}

>>> vet_treatment = {"cats": 2, "dogs": 1}

>>> # Merge dictionaries with .update()

>>> pets = {}

>>> pets.update(for_adoption)

>>> pets.update(vet_treatment)

>>> pets

{'dogs': 1, 'cats': 2, 'pythons': 3}