Python sphinx 无法导入扩展名。。。狮身人面像定向

我正在尝试测试sphinx的扩展TODO

但是，此从docutils.parsers.rst import SphinxDirective导入不起作用，导致扩展错误： 无法导入扩展todo异常：没有名为SphinxDirective的模块

我尝试了python2和python3，并阅读了Docs环境

代码在这里

ReadTheDocs提供了以下信息：

Running Sphinx v1.8.5
loading translations [en]... done

Traceback (most recent call last):
  File "/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/envs/latest/lib/python3.7/site-packages/sphinx/registry.py", line 472, in load_extension
    mod = __import__(extname, None, None, ['setup'])
  File "/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/checkouts/latest/docs/todo.py", line 6, in <module>
    from docutils.parsers.rst import SphinxDirective
ImportError: cannot import name 'SphinxDirective' from 'docutils.parsers.rst' (/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/envs/latest/lib/python3.7/site-packages/docutils/parsers/rst/__init__.py)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/envs/latest/lib/python3.7/site-packages/sphinx/cmd/build.py", line 303, in build_main
    args.tags, args.verbosity, args.jobs, args.keep_going)
  File "/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/envs/latest/lib/python3.7/site-packages/sphinx/application.py", line 228, in __init__
    self.setup_extension(extension)
  File "/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/envs/latest/lib/python3.7/site-packages/sphinx/application.py", line 449, in setup_extension
    self.registry.load_extension(self, extname)
  File "/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/envs/latest/lib/python3.7/site-packages/sphinx/registry.py", line 475, in load_extension
    raise ExtensionError(__('Could not import extension %s') % extname, err)
sphinx.errors.ExtensionError: Could not import extension todo (exception: cannot import name 'SphinxDirective' from 'docutils.parsers.rst' (/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/envs/latest/lib/python3.7/site-packages/docutils/parsers/rst/__init__.py))

Extension error:
Could not import extension todo (exception: cannot import name 'SphinxDirective' from 'docutils.parsers.rst' (/home/docs/checkouts/readthedocs.org/user_builds/demo-sphinx-extensions-for-dirac/envs/latest/lib/python3.7/site-packages/docutils/parsers/rst/__init__.py))

那么

必须使用教程中的正确文件以及所有安装的软件包

这在ReadTheDocs门户上得到了保证，在那里扩展构建工作正常

PS：文件和链接是