我就进入一下python环境就能出现个错误：

Error processing line 1 of D:\Program\Anaconda3\envs\cat\lib\site-packages\matplotlib-3.4.2-py3.7-nspkg.pth:

完整情况如下：

(cat) PS E:\matlab> python
Error processing line 1 of D:\Program\Anaconda3\envs\cat\lib\site-packages\matplotlib-3.4.2-py3.7-nspkg.pth:

  Traceback (most recent call last):
    File "D:\Program\Anaconda3\envs\cat\lib\site.py", line 168, in addpackage
      exec(line)
    File "<string>", line 1, in <module>
    File "<frozen importlib._bootstrap>", line 580, in module_from_spec
  AttributeError: 'NoneType' object has no attribute 'loader'

Remainder of file ignored
Python 3.7.10 | packaged by conda-forge | (default, Feb 19 2021, 15:37:01) [MSC v.1916 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> quit()

我直接卸载并重装matplotlib

pip uninstall matplotlib
pip uninstall matplotlib

再次进入python就正常了。

(cat) PS E:\matlab> python
Python 3.7.10 | packaged by conda-forge | (default, Feb 19 2021, 15:37:01) [MSC v.1916 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>>