我有PyDrive文档中的以下代码，该代码允许访问Google云端硬盘中的顶级文件夹。我想从中访问所有文件夹，子文件夹和文件。我将如何做（我刚刚开始使用PyDrive）？

#!/usr/bin/python
# -*- coding: utf-8 -*-
from pydrive.auth import GoogleAuth
from pydrive.drive import GoogleDrive


gauth = GoogleAuth()
gauth.LocalWebserverAuth() # Creates local webserver and auto handles authentication

#Make GoogleDrive instance with Authenticated GoogleAuth instance
drive = GoogleDrive(gauth)

#Google_Drive_Tree = 
# Auto-iterate through all files that matches this query
top_list = drive.ListFile({'q': "'root' in parents and trashed=false"}).GetList()
for file in top_list:
    print 'title: %s, id: %s' % (file['title'], file['id'])
    print "---------------------------------------------"

#Paginate file lists by specifying number of max results
for file_list in drive.ListFile({'q': 'trashed=true', 'maxResults': 10}):
    print 'Received %s files from Files.list()' % len(file_list) # <= 10
    for file1 in file_list:
        print 'title: %s, id: %s' % (file1['title'], file1['id'])

我已经检查了以下页面如何列出Google驱动器文件夹的所有文件，文件夹，子文件夹和子文件，这似乎是我正在寻找的答案，但是代码不再存在。