code: func (t *Tree) Set(topic string, value interface{}) {
  	t.mutex.Lock()
  	defer t.mutex.Unlock()
  
  	t.set(value, 0, strings.Split(topic, t.Separator), t.root)
  }
docs: // Set sets the supplied value as the only value for the supplied topic. This
  // function will automatically grow the tree.