DWORD mathematical operations in python

Question

I have a C hashing function which I wish to convert to python.

But I am stumped on how to handle the DWORD mathematical operations like following snippets:

DWORD  dwResult = 0
DWORD dwNumValid = strlen(chararray);
...
dwResult = (dwResult << 3) | (dwResult >> (sizeof(DWORD)*8 - 3));
dwResult += somechararray[position];
...
dwHashLocal = dwResult
while (dwHashLocal)
{
  dwNewChar = dwHashLocal % dwNumValid;
  ....
  dwHashLocal /= dwNumValid;
}

I tried playing with import ctypes but am a total noob with byte conversions and operations.

Most of the errors are of sorts unsupported operand type(s) for %: 'c_ulong' and 'c_ulong'

Any pointers would be much appreciated