json walker with reduce func.

main.py

import functools
import operator
import unittest
from typing import List, Union


def reduce_json(data: dict, keys: List[Union[str, int]]):

    if len(keys) == 0:
        return
    try:
        return functools.reduce(operator.getitem, keys, data)
    except (KeyError, IndexError):
        return


class ReduceJsonTests(unittest.TestCase):
    def setUp(self) -> None:
        self.example_data = {
            "pk": 1,
            "personal": {
                "age": 19,
                "first_name": "john",
                "last_name": "doe",
                "address": {
                    "coordinates": {"longitude": "481148", "latitude": "114811"},
                    "city": "new york",
                    "street": "48. street",
                    "raw": "lorem ipsum dolor sit amet.",
                },
            },
        }

    def test_reduce_json_func(self):
        self.assertEqual(
            reduce_json(self.example_data, ["personal", "address", "city"]),
            "new york",
        )
        self.assertEqual(reduce_json(self.example_data, ["personal", "age"]), 19)

        self.assertEqual(reduce_json(self.example_data, ["pk"]), 1)

        self.assertIsNone(reduce_json(self.example_data, ["not_exist_key"]))


if __name__ == "__main__":
    unittest.main()