docs: def reset(self):
          """Reset the barrier to the initial state.
  
          Any threads currently waiting will get the BrokenBarrier exception
          raised.
  
          """
          with self._cond:
              if self._count > 0:
                  if self._state == 0:
                      #reset the barrier, waking up threads
                      self._state = -1
                  elif self._state == -2:
                      #was broken, set it to reset state
                      #which clears when the last thread exits
                      self._state = -1
              else:
                  self._state = 0
              self._cond.notify_all()