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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 batch(self, client=None):
 """Return a batch to use as a context manager. :type client: :class:`~google.cloud.logging.client.Client` or ``NoneType`` :param client: the client to use. If not passed, falls back to the ``client`` stored on the current topic. :rtype: :class:`Batch` :returns: A batch to use as a context manager. """

        client = self._require_client(client)
        return Batch(self, client)