[readme] Should Python 3.10 be mentioned as prerequisite

[kshitij12345]

The readme mentions Python 3.10 as a prerequisite but it gets installed whenever the lp environment is created with conda (as it is mentioned in the environment_{unix|windows}.yaml).

This may confuse new developers to the project (like me) to have a native Python installation even though it is not required.

I think conda should be the only prerequisite.

Thanks!

Ref: https://github.com/lcompilers/lpython#step-0-prerequisites

[certik]

@kshitij12345 CPython is not needed for end users of LPython, unless they want to call into CPython.

For LPython developers however, we need CPython for the following reasons:

• We have some Python scripts to generate C++ code for AST/ASR
• Our test runners (both tests in tests and integration_tests) are implemented in Python
• We test every test in integration_tests in CPython, to ensure it is compatible with it

So you need CPython for developing LPython.

[kshitij12345]

Right, I understand that we need CPython for development.

What I meant was while reading the below instruction

I installed Python 3.10 natively on my system but then in the step below, we do install the required Python 3.10 using conda for the development environment. So essentially the manual installation I did was not required.

conda env create -f environment_unix.yml
conda activate lp

I guess, this may not be a common issue and maybe I followed the instructions incorrectly 😅 , but the instruction seemed a bit confusing to me.

Thanks!

[certik]

Ah I see! We should clarify this. Do you mind submitting a PR fixing this please? That would be very helpful.

[kshitij12345]

Sure, will send a PR soon.