client.py

import requests
import argparse
import getpass
import socket


def get_ip() -> str:
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    try:
        # doesn't even have to be reachable
        s.connect(('10.255.255.255', 1))
        IP = s.getsockname()[0]
    except:
        IP = '127.0.0.1'
    finally:
        s.close()
    return IP


def main():

    parser = argparse.ArgumentParser(description='ip/username sender\n',
                                     epilog='send ip and username to server')

    parser.add_argument('-H', '--host', help="server host")
    parsed_args = parser.parse_args()

    r = requests.post("http://{host}:1234/".format(host=parsed_args.host),
                      data={'ip': get_ip(), 'name': getpass.getuser()})
    # And done.
    print(r.text)  # displays the result body.


if __name__ == '__main__':
    main()