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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def main():
 """ Main entry point for the `respect` command. """

    args = parse_respect_args(sys.argv[1:])
    if validate_username(args['<username>']):
        print("processing...")
    else:
        print("@"+args['<username>'], "is not a valid username.")
        print("Username may only contain alphanumeric ASCII characters or "
              "dashes and cannot begin with a dash.")
        return
    try:
        r = requests.get(urljoin(GITHUB_USERS, args['<username>']))
    except ConnectionErrorException as e:
        print('Connection Error from requests. Request again, please.')
        print(e)

    if r.status_code == 404 or r.status_code == 403:
        session = login(401, args=args)
        return dispatch(args, r, session)

    elif r.status_code == 200:
        return dispatch(args, response=r)
    else:
        raise UnknownStausCodeException