code: func (c *RawBinaryClient) Increment(
  	key string,
  	delta uint64,
  	initValue uint64,
  	expiration uint32) CountResponse {
  
  	c.mutex.Lock()
  	defer c.mutex.Unlock()
  
  	resp := c.sendCountRequest(opIncrement, key, delta, initValue, expiration)
  	if resp != nil {
  		return resp
  	}
  	return c.receiveCountResponse(opIncrement, key)
  }
docs: // See Client interface for documentation.