code: func (c *Client) IntervalById(id string) (interval contract.Interval, err error) {
  	conn := c.Pool.Get()
  	defer conn.Close()
  
  	object, err := redis.Bytes(conn.Do("GET", id))
  	if err == redis.ErrNil {
  		return contract.Interval{}, db.ErrNotFound
  	} else if err != nil {
  		return contract.Interval{}, err
  	}
  
  	err = json.Unmarshal(object, &interval)
  	if err != nil {
  		return contract.Interval{}, err
  	}
  
  	return interval, err
  }
docs: // Return schedule interval by ID