code: def removeReadGroupSet(self, readGroupSet):
          
          for readGroupSetRecord in models.Readgroupset.select().where(
                          models.Readgroupset.id == readGroupSet.getId()):
              readGroupSetRecord.delete_instance(recursive=True)
docs: Removes the specified readGroupSet from this repository. This performs
          a cascading removal of all items within this readGroupSet.