docs: def extendleft(self, iterable):
          """Extend the left side of this GeventDeque by appending
          elements from the iterable argument.  Note, the series of left
          appends results in reversing the order of elements in the
          iterable argument.
          """
          self._deque.extendleft(iterable)
          if len(self._deque) > 0:
              self.notEmpty.set()