code: def acquire_code(args, session, session3):
      
      serial_number = find_mfa_for_user(args.serial_number, session, session3)
      if not serial_number:
          print("There are no MFA devices associated with this user.",
                file=sys.stderr)
          return None, None, USER_RECOVERABLE_ERROR
  
      token_code = args.token_code
      if token_code is None:
          while token_code is None or len(token_code) != 6:
              token_code = getpass.getpass("MFA Token Code: ")
      return serial_number, token_code, OK
docs: returns the user's token serial number, MFA token code, and an
      error code.