def low_latency(self):
op = self.topology.graph.addOperator("<STR_LIT>")<EOL>op.addInputPort(outputPort=self.oport)<EOL>oport = op.addOutputPort(schema=self.oport.schema)<EOL>return Stream(self.topology, oport)<EOL>
The function is guaranteed to run in the same process as the
upstream Stream function. All streams that are created from the returned stream 
are also guaranteed to run in the same process until end_low_latency() 
is called.

Returns:
    Stream