This is an alternate option that worked for me.

The original Python Package site: https://pip.pypa.io/en/stable/installation/ specifies multiple options.

One of them is to use the get-pip.py script - https://pip.pypa.io/en/stable/installation/#get-pip-py. Once we download the script, use the following command (python or python3).

python get-pip.py  --break-system-packages --trusted-host pypi.org --trusted-host files.pythonhosted.org

Without the argument "--break-system-package", it was giving another error which was addressed in another stackoverflow - How do I solve "error: externally-managed-environment" every time I use pip 3? . I used it any way accepting the risk as its isolated to pip. So, use it with caution.

Without the argument "--trusted-host", there is an SSL cert issue and that is addressed in the stackoverflow - pip3 Could not fetch URL https://pypi.org/simple/pip/: There was a problem confirming the ssl certificate