code: func (c *MockProducer) Unregister(eventch chan<- interface{}) {
  	c.Lock()
  	defer c.Unlock()
  
  	for i, e := range c.eventChannels {
  		if e == eventch {
  			if i != 0 {
  				c.eventChannels = c.eventChannels[1:]
  			}
  			c.eventChannels = c.eventChannels[1:]
  			close(eventch)
  			return
  		}
  	}
  }
docs: // Unregister unregisters an event channel