guid.py

import ctypes
import ctypes.wintypes

class GUID(ctypes.Structure):
    _fields_ = [("Data1", ctypes.wintypes.DWORD),
                ("Data2", ctypes.wintypes.WORD),
                ("Data3", ctypes.wintypes.WORD),
                ("Data4", ctypes.c_ubyte * 8)]
    def __repr__(self):
        return "{0:08X}-{1:04X}-{2:04X}-{3:02X}{4:02X}-{5:02X}{6:02X}{7:02X}{8:02X}{9:02X}{10:02X}".format(self.Data1, 
            self.Data2, self.Data3, self.Data4[0], self.Data4[1], self.Data4[2], self.Data4[3], self.Data4[4],
            self.Data4[5], self.Data4[6], self.Data4[7])
    __str__ = __repr__