code: def notifyAppend(self, queue, force):
          '''
          Internal notify for sub-queues
          
          :returns: If the append is blocked by parent, an EventMatcher is returned, None else.
          '''
          if not force and not self.canAppend():
              self.isWaited = True
              return self._matcher
          if self.parent is not None:
              m = self.parent.notifyAppend(self, force)
              if m is not None:
                  return m
          self.totalSize = self.totalSize + 1
          return Nonf notifyAppend(self, queue, force):
          '''
          Internal notify for sub-queues
          
          :returns: If the append is blocked by parent, an EventMatcher is returned, None else.
          '''
          if not force and not self.canAppend():
              self.isWaited = True
              return self._matcher
          if self.parent is not None:
              m = self.parent.notifyAppend(self, force)
              if m is not None:
                  return m
          self.totalSize = self.totalSize + 1
          return None
docs: Internal notify for sub-queues
          
          :returns: If the append is blocked by parent, an EventMatcher is returned, None else.