code: def _process_incoming_presence(self, stanza_obj):
          
          self._logger.debug("incoming presence: %r", stanza_obj)
  
          stanza_obj = self.service_inbound_presence_filter.filter(stanza_obj)
          if stanza_obj is None:
              self._logger.debug("incoming presence dropped by service filter"
                                 " chain")
              return
  
          stanza_obj = self.app_inbound_presence_filter.filter(stanza_obj)
          if stanza_obj is None:
              self._logger.debug("incoming presence dropped by application "
                                 "filter chain")
              return
  
          self.on_presence_received(stanza_obj)
docs: Process an incoming presence stanza `stanza_obj`.