[Python] Creating library using Cython and getting link error [duplicate]

I have to create a windows library from python code. To hide my source code, I want to cythonize the code and create a single library which can be used by everyone.

My folder structure

manager/
├── sample/
│ ├── __init__.py
│ ├── a.py
│ ├── b.py
│ └── c.py
│
│── __init__.py
├── main.py
└── setup.py # For building the shared library


a.py -

class a:
def test(self):
raise NotImplementedError("Subclasses should implement this!")


b.py -

from sample import a

class b(a):
def __init__(self):
return

def test(self):
return True


c.py -

from sample import a

class c(a):
def __init__(self):
return

def test(self):

return True


init.py and main.py are empty files

I am using Visual Studio code.

When I run this command : python setup.py build_ext --inplace , I get error :

LINK : error LNK2001: unresolved external symbol PyInit_sample build\temp.win-amd64-cpython-312\Release\temp_build\sample\sample.cp312-win_amd64.lib : fatal error LNK1120: 1 unresolved externals error: command 'C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.33.31629\bin\HostX86\x64\link.exe' failed with exit code 1120

My setup.py :

from setuptools import setup, Extension
from Cython.Build import cythonize
import os

def find_py_files():
current_dir = os.getcwd() # Use current directory
print(f"Searching for Python files in: {current_dir}")
files = []
for root, _, filenames in os.walk(current_dir):
if 'venv' in root: # Ignore the venv directory
continue
for filename in filenames:
if filename.endswith(".py") and filename != "__init__.py" and filename != "setup.py": # Skip __init__.py files
file_path = os.path.join(root, filename)
print(f"Found: {os.path.relpath(file_path, start=current_dir)}")
files.append(file_path)
return files

temp_build_dir = "temp_build"

# Combine all found Python files into a single extension module
py_files = find_py_files()
if py_files:
extension = Extension(
name = "sample",
sources = py_files,
language='c++'
)

setup(
name='sample',
ext_modules=cythonize(
[extension],
build_dir=temp_build_dir,
),
zip_safe=False,
)
else:
print("No Python files found to compile.")


My issue is that .pyd is only not getting created. The Collapse multiple submodules to one Cython extension tells about import from cython modules after pyd is created

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