code: def indication(self, apdu):
          
          if _debug: ServerSSM._debug("indication %r", apdu)
  
          if self.state == IDLE:
              self.idle(apdu)
          elif self.state == SEGMENTED_REQUEST:
              self.segmented_request(apdu)
          elif self.state == AWAIT_RESPONSE:
              self.await_response(apdu)
          elif self.state == SEGMENTED_RESPONSE:
              self.segmented_response(apdu)
          else:
              if _debug: ServerSSM._debug("    - invalid state")
docs: This function is called for each downstream packet related to
          the transaction.