Using toolz and dispatcher to merge dicts

merge_dicts.py

from functools import singledispatch
from toolz import merge_with

dict_1 = {
    'a': 1,
    'b': 1,
    'c': [
        1, 2, 3, 4
    ],
    'd': {
        'e': 7
    },
    'f': 'test1'
}

dict_2 = {
    'a': 2,
    'b': 2,
    'c': [
        5, 6, 7, 8
    ],
    'd': {
        'e': 9
    },
    'f': 'test2'

}


@singledispatch
def merge_function(d1, d2):
    ...


@merge_function.register(list)
def _(d1, d2):
    return d1 + d2


@merge_function.register(int)
def _(d1, d2):
    return d1


@merge_function.register(dict)
def _(d1, d2):
    return merge_with(merge_interface, d1, d2)


@merge_function.register(str)
def _(d1, d2):
    return d1


def merge_interface(x):
    dict_1_arg, dict_2_arg = x
    return merge_function(dict_1_arg, dict_2_arg)


print(merge_with(merge_interface, dict_1, dict_2))
print(merge_with(merge_interface, dict_2, dict_1))