Jupyter notebook 通知启动错误：无法导入名称'；元数据'；从'；importlib'；

在卸载和更新sklearn库后，我无法启动jupyter笔记本 如下

conda uninstall scikit-learn --yes
conda install scikit-learn==0.23.1

我无法通过单击jupyter笔记本启动按钮从ANACONDA NAGIGATOR启动我的jupyter笔记本。 应用程序启动错误显示

Traceback (most recent call last):
File "D:\Anaconda3\lib\site-packages\jsonschema\__init__.py", line 31, in 
from importlib import metadata
ImportError: cannot import name 'metadata' from 'importlib' (D:\Anaconda3\lib\importlib\__init__.py)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "D:\Anaconda3\Scripts\jupyter-notebook-script.py", line 6, in 
from notebook.notebookapp import main
File "D:\Anaconda3\lib\site-packages\notebook\notebookapp.py", line 85, in 
from .services.contents.manager import ContentsManager
File "D:\Anaconda3\lib\site-packages\notebook\services\contents\manager.py", line 17, in 
from nbformat import sign, validate as validate_nb, ValidationError
File "D:\Anaconda3\lib\site-packages\nbformat\__init__.py", line 32, in 
from .validator import validate, ValidationError
File "D:\Anaconda3\lib\site-packages\nbformat\validator.py", line 12, in 
from .json_compat import get_current_validator, ValidationError
File "D:\Anaconda3\lib\site-packages\nbformat\json_compat.py", line 10, in 
import jsonschema
File "D:\Anaconda3\lib\site-packages\jsonschema\__init__.py", line 33, in 
import importlib_metadata as metadata
ModuleNotFoundError: No module named 'importlib_metadata'

有人知道如何解决这个问题吗？

如果你在外壳中键入“conda list anaconda”，它会说什么？如果你在外壳中键入“conda list anaconda”，它会说什么？