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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 update_active_id_list(self, update_active_ids_finished_cb):
 """Request an update of the active id list"""

        if not self._update_active_ids_finished_cb:
            self._update_active_ids_finished_cb = update_active_ids_finished_cb
            self.active_anchor_ids = []

            self.active_ids_valid = False

            logger.debug('Updating active ids of memory {}'.format(self.id))

            # Start reading the header
            self.mem_handler.read(self, LocoMemory2.ADR_ACTIVE_ID_LIST,
                                  LocoMemory2.ID_LIST_LEN)