[Python] Import .pyd Python module

I realized a C++ project and I used pydbind11. All work fine on Linux (C++ compilation with CMake produces test executables and Python module that works when I import it, installation with pip install works too). On Windows, I compile the project with MSYS2 UCRT64 in a MSYS2 UCRT64 prompt. To launch .exe files, I need to launch them in a CMD prompt instead of a MSYS2 UCRT64 prompt, I don't know why. The compilation produces a .pyd file in build folder but I don't arrive to import it. I create a symreg folder at root project and I copy the .pyd file into with the appropriate DLL files. I try too with a __init__.py file with the following content:

from .symreg import *


Here is the output in MSYS2 UCRT64 prompt:

Julien@DESKTOP-0IQSQEO UCRT64 ~/symreg_ws/SymReg
$ ls symreg/
__init__.py libblas.dll libglog-2.dll libstdc++-6.dll zlib1.dll
__pycache__ libceres-4.dll libgvc-6.dll libwinpthread-1.dll
libarmadillo.dll libgcc_s_seh-1.dll libopenblas.dll symreg.cp312-win_amd64.pyd

Julien@DESKTOP-0IQSQEO UCRT64 ~/symreg_ws/SymReg
$ python
Python 3.12.11 (main, Jun 7 2025, 12:31:34) [GCC UCRT 15.1.0 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import symreg
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "D:/Programmes/msys64/home/Julien/symreg_ws/SymReg/symreg/__init__.py", line 1, in <module>
from .symreg import *
ModuleNotFoundError: No module named 'symreg.symreg'


Here is the output in CMD prompt:

D:\Programmes\msys64\home\Julien\symreg_ws\SymReg>D:\Programmes\msys64\ucrt64\bin\python.exe
Python 3.12.11 (main, Jun 7 2025, 12:31:34) [GCC UCRT 15.1.0 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import symreg
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "D:\Programmes\msys64\home\Julien\symreg_ws\SymReg\symreg\__init__.py", line 1, in <module>
from .symreg import *
ModuleNotFoundError: No module named 'symreg.symreg'


Have you any idea to use this .pyd file correctly? And then of course, install it to use it in Python scripts?

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