code: func UpdateCMSketch(c *CMSketch, eqFeedbacks []Feedback) *CMSketch {
  	if c == nil || len(eqFeedbacks) == 0 {
  		return c
  	}
  	newCMSketch := c.Copy()
  	for _, fb := range eqFeedbacks {
  		newCMSketch.updateValueBytes(fb.Lower.GetBytes(), uint64(fb.Count))
  	}
  	return newCMSketch
  }
docs: // UpdateCMSketch updates the CMSketch by feedback.