Given a first name and last name and domain, generate probable permutations for email address

email-gen.py

#!/usr/bin/env python3
import click


@click.command()
@click.option('--first')
@click.option('--last')
@click.option('--domain')
@click.option('--middle', default=None)
def main(first, last, domain, middle):
    first_init = first[0]
    middle_init = middle[0] if middle else ''
    for sep in ('.', '_', '-', ''):
        print(f'{first}{sep}{last}@{domain}')
        print(f'{last}{sep}{first}@{domain}')
        print(f'{first_init}{sep}{last}@{domain}')
        print(f'{last}{sep}{first_init}@{domain}')


if __name__ == '__main__':
    main()