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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 complete(self, stream):
 """Complete the pending stream. Any connections made to :py:attr:`stream` are connected to `stream` once this method returns. Args: stream(Stream):
 Stream that completes the connection. """

            assert not self.is_complete()
            self._marker.addInputPort(outputPort=stream.oport)
            self.stream.oport.schema = stream.oport.schema
            # Update the pending schema to the actual schema
            # Any downstream filters that took the reference
            # will be automatically updated to the correct schema
            self._pending_schema._set(self.stream.oport.schema)

            # Mark the operator with the pending stream
            # a start point for graph travesal
            stream.oport.operator._start_op = True