You expect this is a large document? No, it's quite short:

1. spago build
2. py call ps: python -c "from <your project name>.Main.pure import main;main()"
3. ps call py: foreign import <variable> : <type>.

You can extract the generated Python package out, and encapsulate it as a standalone Python package, and upload to PyPI.

Moreover, given such a PS module A.B:

module A.B(export1, export2) where
...

In Python, you can import export1 by

import <your project name>.A.B.pure as AB
AB.export1 # you got it

This is also a reason why PureScript is pragmatic, because it uses the same calling convention as Python's.

It supports tail call optimizations, e.g., a purescript function like

f x y = x + y

can be used in Python in this way:

assert f(1)(2) == 3

For each project, if your project directory tree is

- src
    - Main.purs
    - Mod
        - A.purs

If you have foreign definitions in module Mod.A, such as in src/Mod/A.purs:

module Mod.A where
foreign import add233 : Int -> Int

then you need to create a directory python-ffi juxtaposing src, and it'll finally look like:

- python-ffi
   - Mod
      - A.py
- src
    - Main.purs
    - Mod
        - A.purs

In python-ffi/Mod/A.py:

def add233(x):
    return x + 233