ModuleNotFoundError during pip install when module is actually installed

问题

I tried installing a python package (BentoML) using pip install bentoml, and I received the following error, which gives a ModuleNotFoundError: No module named 'wrapt'. However, the wrapt module is actually included in my site-packages folder, so a pip install wrapt results in the message that I already have wrapt installed.

I can install other packages using pip, but the alembic package causes this issue. I was able to install using pip using my Anaconda Python, but I want it installed with this Python version. What is the best way forward?

I'm using Python 3.8.1 on a Windows 10 device.

  ERROR: Command errored out with exit status 1:
   command: 'c:\users\username\appdata\local\programs\python\python38\python.exe' 'c:\users\username\appdata\local\programs\python\python38\lib\site-packages\pip\_vendor\pep517\_in_process.py' get_requires_for_build_wheel 'C:\Users\user~1.lastname\AppData\Local\Temp\tmpd30adik_'
       cwd: C:\Users\username\AppData\Local\Temp\pip-install-qers2adl\alembic
  Complete output (14 lines):
  Fatal Python error: init_import_size: Failed to import the site module
  Python runtime state: initialized
  Traceback (most recent call last):
    File "c:\users\username\appdata\local\programs\python\python38\lib\site.py", line 580, in <module>
      main()
    File "c:\users\username\appdata\local\programs\python\python38\lib\site.py", line 573, in main
      execsitecustomize()
    File "c:\users\username\appdata\local\programs\python\python38\lib\site-packages\certifi_win32\bootstrap.py", line 37, in _execsitecustomize
      _register_bootstrap_functions()
    File "c:\users\username\appdata\local\programs\python\python38\lib\site-packages\certifi_win32\bootstrap.py", line 25, in _register_bootstrap_functions
      from . import wrapt_certifi
    File "c:\users\username\appdata\local\programs\python\python38\lib\site-packages\certifi_win32\wrapt_certifi.py", line 3, in <module>
      import wrapt
  ModuleNotFoundError: No module named 'wrapt'
  ----------------------------------------
ERROR: Command errored out with exit status 1: 'c:\users\username\appdata\local\programs\python\python38\python.exe' 'c:\users\username\appdata\local\programs\python\python38\lib\site-packages\pip\_vendor\pep517\_in_process.py' get_requires_for_build_wheel 'C:\Users\user~1.lastname\AppData\Local\Temp\tmpd30adik_' Check the logs for full command output.

回答1:

Install using another version of Python. Open up an Anaconda prompt (or another version of Python on the same device), and run:

pip install alembic --target="c:\users\username\appdata\local\programs\python\python38\lib\site-packages"

This was the same approach I used when I broke Python after trying to uninstall/reinstall wrapt. The other Python version installs alembic to the correct location and the original install works.

来源：https://stackoverflow.com/questions/62680281/modulenotfounderror-during-pip-install-when-module-is-actually-installed