<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def pb_id(self, pb_id: str):
 """Set the PB Id for this device."""

        # FIXME(BMo) instead of creating the object to check if the PB exists
        #            use a method on PB List?
        # ProcessingBlock(pb_id)
        self.set_state(DevState.ON)
        self._pb_id = pb_id