尝试运行/启动 Flask 应用程序时出现 python 导入错误

Question

My Flask Application was working alright and all of a sudden I am seeing this error when I run the command to launch the App locally.

File "/Flask_Trial_App2/index.py", line 6, in <module>
    import pandas as pd
  File "/Flask_Trial_App/virt/lib/python3.8/site-packages/pandas/__init__.py", line 16, in <module>
    raise ImportError(
ImportError: Unable to import required dependencies:
numpy: 

IMPORTANT: PLEASE READ THIS FOR ADVICE ON HOW TO SOLVE THIS ISSUE!

Importing the numpy C-extensions failed. This error can happen for
many reasons, often due to issues with your setup or how NumPy was
installed.

We have compiled some common reasons and troubleshooting tips at:

    https://numpy.org/devdocs/user/troubleshooting-importerror.html

Please note and check the following:

  * The Python version is: Python3.8 from "/Flask_Trial_App/virt/bin/python"
  * The NumPy version is: "1.21.1"

and make sure that they are the versions you expect.
Please carefully study the documentation linked above for further help.

Original error was: No module named 'numpy.core._multiarray_umath'

I tried upgrading pandas and numpy , but it didn't fix the issue.

pip install --upgrade numpy
pip install --upgrade pandas

Answer 1

I've had similar issues to this when deploying flask apps on servers with different environments, here is something I've done that worked in the past in case this helps:

Uninstall the package then reinstall specific version using the absolute path to the python executable.

/Flask_Trial_App/virt/bin/python3 -m pip uninstall numpy; /Flask_Trial_App/virt/bin/python3 -m pip install numpy==1.21.1

Hope that may help.