code: def collection_name(self, value):
          
          self._collection_name = value
          self._mongo_coll = self.db[value]
          self.collection = TrackedCollection(self._mongo_coll, operation=self._t_op,
                                              field=self._t_field)
docs: Switch to another collection.
          Note that you may have to set the aliases and default properties if the
          schema of the new collection differs from the current collection.