<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def getExperiment(self):
 """ Returns the GA4GH protocol representation of this read group's Experiment. """

        experiment = protocol.Experiment()
        experiment.id = self.getExperimentId()
        experiment.instrument_model = pb.string(self.getInstrumentModel())
        experiment.sequencing_center = pb.string(self.getSequencingCenter())
        experiment.description = pb.string(self.getExperimentDescription())
        experiment.library = pb.string(self.getLibrary())
        experiment.platform_unit = pb.string(self.getPlatformUnit())
        experiment.message_create_time = self._iso8601
        experiment.message_update_time = self._iso8601
        experiment.run_time = pb.string(self.getRunTime())
        return experiment