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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 commit(self):
 """ Commit the offset of the message we last processed if it is different from what we believe is the last offset committed to Kafka. .. note:: It is possible to commit a smaller offset than Kafka has stored. This is by design, so we can reprocess a Kafka message stream if desired. On error, will retry according to :attr:`request_retry_max_attempts` (by default, forever). If called while a commit operation is in progress, and new messages have been processed since the last request was sent then the commit will fail with :exc:`OperationInProgress`. The :exc:`OperationInProgress` exception wraps a :class:`~twisted.internet.defer.Deferred` which fires when the outstanding commit operation completes. :returns: A :class:`~twisted.internet.defer.Deferred` which resolves with the committed offset when the operation has completed. It will resolve immediately if the current offset and the last committed offset do not differ. """

        # Can't commit without a consumer_group
        if not self.consumer_group:
            return fail(Failure(InvalidConsumerGroupError(
                "Bad Group_id:{0!r}".format(self.consumer_group))))
        # short circuit if we are 'up to date', or haven't processed anything
        if ((self._last_processed_offset is None) or
                (self._last_processed_offset == self._last_committed_offset)):
            return succeed(self._last_committed_offset)

        # If we're currently processing a commit we return a failure
        # with a deferred we'll fire when the in-progress one completes
        if self._commit_ds:
            d = Deferred()
            self._commit_ds.append(d)
            return fail(OperationInProgress(d))

        # Ok, we have processed messages since our last commit attempt, and
        # we're not currently waiting on a commit request to complete:
        # Start a new one
        d = Deferred()
        self._commit_ds.append(d)

        # Send the request
        self._send_commit_request()

        # Reset the commit_looper here, rather than on success to give
        # more stability to the commit interval.
        if self._commit_looper is not None:
            self._commit_looper.reset()

        # return the deferred
        return d