code: func (s *Collector) Unsubscribe(c *container.Container, ch chan interface{}) {
  	s.m.Lock()
  	publisher := s.publishers[c]
  	if publisher != nil {
  		publisher.Evict(ch)
  		if publisher.Len() == 0 {
  			delete(s.publishers, c)
  		}
  	}
  	s.m.Unlock()
  }
docs: // Unsubscribe removes a specific subscriber from receiving updates for a container's stats.