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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 subscribe_to_orders(self, order_filter=None, initial_clk=None, clk=None, conflate_ms=None, heartbeat_ms=None, segmentation_enabled=True):
 """ Order subscription request. :param dict order_filter: Order filter to be applied :param str initial_clk: Sequence token for reconnect :param str clk: Sequence token for reconnect :param int conflate_ms: conflation rate (bounds are 0 to 120000) :param int heartbeat_ms: heartbeat rate (500 to 5000) :param bool segmentation_enabled: allow the server to send large sets of data in segments, instead of a single block """

        unique_id = self.new_unique_id()
        message = {
            'op': 'orderSubscription',
            'id': unique_id,
            'orderFilter': order_filter,
            'initialClk': initial_clk,
            'clk': clk,
            'conflateMs': conflate_ms,
            'heartbeatMs': heartbeat_ms,
            'segmentationEnabled': segmentation_enabled,
        }
        if initial_clk and clk:
            # if resubscribe only update unique_id
            self.listener.stream_unique_id = unique_id
        else:
            self.listener.register_stream(unique_id, 'orderSubscription')
        self._send(message)
        return unique_id