Filemapping between python and c++: File not found

Question

I want to send data from a python script to a c++ application via file mapping. However, my c++ application does not find the python file.

Here is my code:

Python:

with mmap.mmap(-1, 4048, tagname="test", access=mmap.ACCESS_WRITE) as mm:
    mm.write(b"Hello world!")

and the c++ code:

TCHAR szName[] = TEXT("test");

HANDLE hMapFile;
LPCTSTR pBuf;

hMapFile = OpenFileMapping(
    FILE_MAP_READ,   // read/write access
    FALSE,                 // do not inherit the name
    szName);               // name of mapping object

if (hMapFile == NULL)
{
    DWORD test = GetLastError();
    _tprintf(TEXT("Could not open file mapping object (%d).\n"),
        GetLastError());
   
}

here I am receiving the Error "ERROR_FILE_NOT_FOUND".

Any ideas what I am doing wrong?

Thanks a lot for any answer!