How to prevent pip from installing a package if it has been installed by conda already

Question

I'm experimenting with my python package. I use anaconda and, inside my environment, I have packages that I need already installed:

conda list | egrep "rdkit|numpy" returns

numpy                     1.19.2           py39h89c1606_0  
numpy-base                1.19.2           py39h2ae0177_0  
rdkit                     2022.03.1b1.0    py39he30056e_1    rdkit/label/beta

My setup.py has two dependencies without specifying versions:

install_requires=[
    'rdkit',
    'numpy',
],

But when I run pip install . it installs another version of rdkit

Collecting rdkit
  Using cached rdkit-2022.3.4-cp39-cp39-manylinux_2_17_x86_64.manylinux2014_x86_64.whl (22.9 MB)

The question is, how to prevent pip from such behavior? I want something like: if a package has already been installed, whatever the version, just keep it and do nothing.

Answer 1

You could try:

pip install --no-cache-dir

to avoid cached versions.

Check this link, it might have what you need:

pip uses incorrect cached package version, instead of the user-specified version