def insort_event_right(self, event, lo=0, hi=None):
    if lo < 0:
      raise ValueError('lo must be non-negative')
    if hi is None:
      hi = len(self.queue)
    while lo < hi:
      mid = (lo + hi) // 2
      if event[0] < self.queue[mid][0]:
        hi = mid
      else:
        lo = mid + 1
    self.queue.insert(lo, event)