What CPython modules are Pure and what ones are C-based?

pure.py

_original_import = __import__


def store_loader(name, module, storage):
    try:
        spec = module.__spec__
        loader = spec.loader if type(spec.loader) == type else spec.loader.__class__
    except Exception as err:
        loader = type(err)
        module = err
    storage.setdefault(loader, {})[name] = module
    return loader


def print_stats(storage):
    for k, v in storage.items():
        print(f'Items: {len(v)} \t\tLoader: {k}')


by_loader = {}


def _import(name, *args, **kwargs):
    print(f'Importing: {name}')
    result = _original_import(name, *args, **kwargs)
    print(f'Imported: {name} -> {result}')
    loader = store_loader(name, result, by_loader)
    return result


__builtins__.__import__ = _import

import importlib
from stdlib_list import stdlib_list

for modname in stdlib_list('3.7'):
    try:
        m = importlib.import_module(modname)
    except ImportError:
        pass

print('\n\nAfter importing\n\n')
print_stats(by_loader)

import sys
for name, module in sys.modules.items():
    store_loader(name, module, by_loader)

print('\n\nAfter inspecting\n\n')
print_stats(by_loader)

from pprint import pprint

print('\n\nModules by loader:\n\n')
pprint(by_loader)

pprint('\n\nSummary:\n\n')
for loader, modules in by_loader.items():
    print(f'\nLoader: {loader}\n')
    for module in sorted(modules):
        print(f'\t{module}')

print('\n\nModules by loader:\n\n')
print_stats(by_loader)