code: def interfacesFor(self, powerup):
          
          pc = _PowerupConnector
          for iface in self.store.query(pc,
                                        AND(pc.item == self,
                                            pc.powerup == powerup)).getColumn('interface'):
              yield namedAny(iface)
docs: Return an iterator of the interfaces for which the given powerup is
          installed on this object.
  
          This is not implemented for in-memory powerups.  It will probably fail
          in an unpredictable, implementation-dependent way if used on one.