Python3 project coding style example.

py_project_coding_style_example.py

#!/usr/bin/env python3

from typing import Union, Optional, Dict


def multiply(arg1: Union[int, float, str, None] = 0.0,
             arg2: Union[int, float, str, None] = 0.0) -> Optional[Dict[str, Union[int, float, str]]]:
    """
    Calculate the product of two numbers.
    :param arg1:    a factor (default: 0.0)
    :param arg2:    a factor (default: 0.0)
    :return:        return None if an input number is None, else
                    return a Dictionary like {'int': 3, 'float': 3.14, 'str': '3.14'}
    """
    if None in (arg1, arg2):
        return None
    result = float(arg1) * float(arg2)
    return {'int': int(result), 'float': result, 'str': str(result)}


def main():
    pass


if __name__ == '__main__':
    main()