Complex dictionary to JSON

dict_15_json.py

import json
from datetime import datetime


class PythonObjectEncoder(json.JSONEncoder):

    def default(self, an_object_value):

        if isinstance(an_object_value, str):
            return an_object_value

        try:
            iterable = iter(an_object_value)
            return list(iterable)
        except TypeError:
            pass  # this object is not iterable

        if isinstance(an_object_value, datetime):
            return an_object_value.isoformat()

        elif hasattr(an_object_value, "__class__"):
            return an_object_value.__dict__

        return super().default(an_object_value)


def dict_to_json(the_dict: dict) -> str:

    return PythonObjectEncoder().encode(the_dict)


class SimpleClass:
    def __init__(self):
        self.instance_value = 10


b = SimpleClass()

dict1: dict = {}
dict1["string"] = "Hello, World!"
dict1["datetime"] = datetime(2030, 12, 31)
dict1["nothing"] = None
dict1["set"]: set = {0, 1, 2, 3}
dict1["tuple"] = ("apples", "fresh", "green")
dict1["list"] = ["a", "b", "c"]
dict1["simple_class"] = SimpleClass()

assert (
        dict_to_json(dict1) ==
            (
                '{"string": "Hello, World!",' 
                ' "datetime": "2030-12-31T00:00:00",'
                ' "nothing": null,'
                ' "set": [0, 1, 2, 3],'
                ' "tuple": ["apples", "fresh", "green"],'
                ' "list": ["a", "b", "c"],'
                ' "simple_class": {"instance_value": 10}}'
            )
    )