将树列表转换为层次结构dict

def tree_to_dict(tree):
    if not tree:
        return {}
    root = tree[0]
    children = [node for node in tree[1:] if node.parent_id == root.id]
    return {
        'id': root.id,
        'name': root.name,
        'children': [tree_to_dict(child) for child in children]
    }

def tree_to_dict(tree):
    if not tree:
        return {}
    stack = [tree[0]]
    result = {}
    while stack:
        node = stack.pop()
        children = [child for child in tree if child.parent_id == node.id]
        result[node.id] = {
            'id': node.id,
            'name': node.name,
            'children': [child.id for child in children]
        }
        stack.extend(children)
    return result