Find duplicate email

email_unique.py

import click
import re
from collections import OrderedDict


def format_email(email, name):
    if name is None:
        return "<%s>" % email
    else:
        return "%s <%s>" % (name, email)


@click.command()
@click.argument('emails')
@click.option('--sep_in', help='Email separator (in)', default=", ")
@click.option('--sep_out', help='Email separator (out)', default=", ")
def main(emails, sep_in, sep_out):
    lst_emails = emails.split(sep_in)
    lst_emails = list(map(lambda s: s.strip(), lst_emails))
    pattern = '(?:"?([^"]*)"?\s)?(?:<?(.+@[^>]+)>?)'

    d_emails = OrderedDict()
    lst_duplicate_emails = []

    for s_name_email in lst_emails:
        match = re.search(pattern, s_name_email)
        s_name, s_email = match.groups()
        if s_email not in d_emails:
            d_emails[s_email] = s_name
        else:
            lst_duplicate_emails.append(s_name_email)

    n_emails = len(lst_emails)
    n_emails_uniq = len(d_emails)
    n_duplicates = n_emails - n_emails_uniq

    lst_emails = list(map(lambda t: format_email(t[0], t[1]),
                      d_emails.items()))

    print("")
    print("Emails: %d" % n_emails)
    print("Duplicate(s): %d" % n_duplicates)
    print(lst_duplicate_emails)
    print("Emails (unique): %d" % n_emails_uniq)
    print("")
    s = sep_out.join(lst_emails)
    print(s)


if __name__ == '__main__':
    main()