Python code completion IntelliSense using Singularity container interpreter

Question

I have made a file python and made it executable chmod +x python

singularity exec instance://pytorch python "$@"

so that I can treat this python file as a python binary, passing any parameters passed to it will be delegated to the python installed in the running instance.

Now to make vscode point to this interpreter, I had to make settings.json inside .vscode folder

{
    "python.pythonPath": "./python"
}

It works fine and I am able to run the script directly on this interpreter. But I can't get autocomplete to work. Why doesn't it work and how do I make it work?