【发布时间】：2021-01-12 11:48:44
【问题描述】：
当我使用pypy3的pip安装jupyter时，它并不总是有效。
pip install jupyter
我使用的pypy版本是pypy3.7-v7.3.3-win32。
安装jupyter时，总是抛出AttributeError，像这样：
Collecting nbclient<0.6.0,>=0.5.0
Using cached https://pypi.tuna.tsinghua.edu.cn/packages/fd/4f/5cbd9bdb30bfaad620f028711bf232b9cec8fdff1dcf68d9259254fcddeb/nbclient-0.5.1-py3-none-any.whl (65 kB)
ERROR: Exception:
Traceback (most recent call last):
File "d:\myapps\pypy37\site-packages\pip\_internal\cli\base_command.py", line 224, in _main
status = self.run(options, args)
File "d:\myapps\pypy37\site-packages\pip\_internal\cli\req_command.py", line 180, in wrapper
return func(self, options, args)
File "d:\myapps\pypy37\site-packages\pip\_internal\commands\install.py", line 321, in run
reqs, check_supported_wheels=not options.target_dir
File "d:\myapps\pypy37\site-packages\pip\_internal\resolution\resolvelib\resolver.py", line 122, in resolve
requirements, max_rounds=try_to_avoid_resolution_too_deep,
File "d:\myapps\pypy37\site-packages\pip\_vendor\resolvelib\resolvers.py", line 445, in resolve
state = resolution.resolve(requirements, max_rounds=max_rounds)
File "d:\myapps\pypy37\site-packages\pip\_vendor\resolvelib\resolvers.py", line 344, in resolve
success = self._backtrack()
File "d:\myapps\pypy37\site-packages\pip\_vendor\resolvelib\resolvers.py", line 287, in _backtrack
criterion = self.state.criteria[name].excluded_of([candidate])
AttributeError: 'NoneType' object has no attribute 'excluded_of'
我该如何解决这个问题？
【问题讨论】：