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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 _find_group_coordinator_id(self, group_id):
 """Find the broker node_id of the coordinator of the given group. Sends a FindCoordinatorRequest message to the cluster. Will block until the FindCoordinatorResponse is received. Any errors are immediately raised. :param group_id: The consumer group ID. This is typically the group name as a string. :return: The node_id of the broker that is the coordinator. """

        # Note: Java may change how this is implemented in KAFKA-6791.
        #
        # TODO add support for dynamically picking version of
        # GroupCoordinatorRequest which was renamed to FindCoordinatorRequest.
        # When I experimented with this, GroupCoordinatorResponse_v1 didn't
        # match GroupCoordinatorResponse_v0 and I couldn't figure out why.
        gc_request = GroupCoordinatorRequest[0](group_id)
        gc_response = self._send_request_to_node(self._client.least_loaded_node(), gc_request)
        # use the extra error checking in add_group_coordinator() rather than
        # immediately returning the group coordinator.
        success = self._client.cluster.add_group_coordinator(group_id, gc_response)
        if not success:
            error_type = Errors.for_code(gc_response.error_code)
            assert error_type is not Errors.NoError
            # Note: When error_type.retriable, Java will retry... see
            # KafkaAdminClient's handleFindCoordinatorError method
            raise error_type(
                "Could not identify group coordinator for group_id '{}' from response '{}'."
                .format(group_id, gc_response))
        group_coordinator = self._client.cluster.coordinator_for_group(group_id)
        # will be None if the coordinator was never populated, which should never happen here
        assert group_coordinator is not None
        # will be -1 if add_group_coordinator() failed... but by this point the
        # error should have been raised.
        assert group_coordinator != -1
        return group_coordinator