Python packages hash not matching whilst installing using pip

The problem here is the Python package was updated with new hash value while pip was trying to install the Python package using the old hash value cached in pip cache directory. This cache needs to be purge before the pip install attempt. So the full solution is:

python -m pip cache purge
python -m pip install <package>

There is a similar problem (Why does pip fail with bad md5 hash for package?) from 2013 the solution that I tried that worked for me is this:

sudo pip install --no-cache-dir flask

given by attolee