Example function to generate a random password

password_generator.py

from random import choice, shuffle
from string import ascii_lowercase, ascii_uppercase, digits


def generate_password(length=16, groups=[ascii_lowercase, ascii_uppercase, digits]):
    """Generate a random strong password.

    It will be of length `length`, with at least one character of each of the `groups`.
    """
    group_indices = list(range(len(groups)))
    chosen_indices = [choice(group_indices) for _ in range(length - len(groups))]
    chosen_indices.extend(group_indices)  # at least one of each
    shuffle(chosen_indices)  # need to shuffle because of the above's fixed position
    return ''.join(choice(groups[index]) for index in chosen_indices)


if __name__ == '__main__':
    print(f'Your new generated password is: {generate_password()}')