docs: def compare(self):  # pylint: disable=no-self-use
          """
          Computes the difference between the candidate config and the running config.
          """
          # becuase we emulate the configuration history
          # the difference is between the last committed config and the running-config
          running_config = self._download_running_config()
          running_config_lines = running_config.splitlines()
          last_committed_config = self._last_working_config
          last_committed_config_lines = last_committed_config.splitlines()
          difference = difflib.unified_diff(running_config_lines, last_committed_config_lines, n=0)
          return '\n'.join(difference)