code: def install_key(self, key_data):
          
          logger.info(("importing repository signing key {0} "
                       "{1}".format(self.key_info['fingerprint'],
                                    self.key_info['uids'][0])))
          import_result = self.gpg.import_keys(key_data)
          logger.debug("import results: {0}".format(import_result.results))
docs: Install untrusted repo signing key