When does Python need to use a compiler?

[JanOlvegg]

OK, after reading your post, I did some digging. If I research this properly, a package in python are not compiled and third party non-python code are setup as "wheels" (I was wondering what wheels were). While python code do not need to be compile, the wheels probably might need compiiling.

Packages like Conda appears to precompile their code, so you would have different packages for different platform (ARM and x86 for example).

Does this sound right?
If conda doesn't have the package, can you compile your own? Thanks.