code: def _add_out_streams(self, spbl):
      
      if self.outputs is None:
        return
  
      # sanitize outputs and get a map <stream_id -> out fields>
      output_map = self._sanitize_outputs()
  
      for stream_id, out_fields in output_map.items():
        out_stream = spbl.outputs.add()
        out_stream.stream.CopyFrom(self._get_stream_id(self.name, stream_id))
        out_stream.schema.CopyFrom(self._get_stream_schema(out_fields))
docs: Adds outputs to a given protobuf Bolt or Spout message