How to use ctypes with Windows?

Question

I'm trying to use some mathematical functions I wrote in C in Python. I have a CMakeLists.txt that builds a shared library using the code. When I build the library in linux and generate the .so library, it works fine. However when I use Windows to generate the .dll library, ctypes says the function doesn't exist.

tools.c

#include "tools.h"

unsigned long long gcd(unsigned long long a, unsigned long long b) {
    if (a == 0 || b == 0){
        return 0;
    }
    else if (a == b) {
        return a;
    }
    else if (a > b) {
        return gcd(a - b, b);
    }
    return gcd(a, b - a);
}

unsigned long long factorial(int n){
    if(n == 0){
        return 1;
    }
    unsigned long long total = 1;
    for(int i = 1; i <= n; i++){
        total *= i;
    }
    return total;
}

tools.h

#ifndef CPYTHON1_TOOLS_H
#define CPYTHON1_TOOLS_H

unsigned long long gcd(unsigned long long a, unsigned long long b);
unsigned long long factorial(int n);

#endif //CPYTHON1_TOOLS_H

CMakeLists.txt

cmake_minimum_required(VERSION 3.16)
project(washmath VERSION 1.0.0)

set(CMAKE_CXX_STANDARD 17)

add_library(${PROJECT_NAME} SHARED tools.c tools.h)

set_target_properties(${PROJECT_NAME} PROPERTIES VERSION ${PROJECT_VERSION})

set_target_properties(${PROJECT_NAME} PROPERTIES SOVERSION ${PROJECT_VERSION_MAJOR})

set_target_properties(${PROJECT_NAME} PROPERTIES PUBLIC_HEADER tools.h)

test.py

from ctypes import CDLL
from ctypes.util import find_library


def main():
    c_lib = CDLL(find_library("./washmath"))
    print(c_lib.factorial(5))


if __name__ == "__main__":
    main()

Linux Output: 120
Windows Output:

File "test.py", line 7, in main
    print(c_lib.factorial(5))
  File "D:\Program Files\Python\Python310\Lib\ctypes\__init__.py", line 387, in __getattr__
    func = self.__getitem__(name)
  File "D:\Program Files\Python\Python310\Lib\ctypes\__init__.py", line 392, in __getitem__
    func = self._FuncPtr((name_or_ordinal, self))
AttributeError: function 'factorial' not found