Dynamic injected value

inject_decorator.py

import functools
import random
import typing

def decorator(
    field_name: str = 'injected_field'
):

    def inner(func: typing.Callable):

        @functools.wraps(func)
        def _inner(
            required1,
            required2,
            *args,
            **kwargs
        ):

            if field_name not in kwargs:
                # Actually, we can generate default value by other ways. 
                # ex. Call other functions, and use its return value.
                kwargs[field_name] = random.randint(1, 100)
            return func(
                required1,
                required2,
                *args,
                **kwargs
            )

        return _inner

    return inner

@decorator()
def func1(
    required1,
    required2,
    *,
    injected_field = None
):
    print(injected_field)

func1(1, 2, injected_field=5)
func1(1, 2, injected_field=6)
func1(1, 2)
func1(1, 2)