code: func (trie *Trie) Get(key Prefix) (item Item) {
  	_, node, found, leftover := trie.findSubtree(key)
  	if !found || len(leftover) != 0 {
  		return nil
  	}
  	return node.item
  }
docs: // Get returns the item located at key.
  //
  // This method is a bit dangerous, because Get can as well end up in an internal
  // node that is not really representing any user-defined value. So when nil is
  // a valid value being used, it is not possible to tell if the value was inserted
  // into the tree by the user or not. A possible workaround for this is not to use
  // nil interface as a valid value, even using zero value of any type is enough
  // to prevent this bad behaviour.