Python: Use the value of a variable for calling another variable

[Carpetsmoker]

My code (simplified):

import _winreg as winreg

SetRegistry(winreg.HKEY_LOCAL_MACHINE, key, values)

def SetRegistry(reg, key, values):
  reghandle = winreg.ConnectRegistry(None, reg)

This works, but I would like to pass HKEY_LOCAL_MACHINE as a string because I want to make a backup of changed registry settings, but how do I pass this on to ConnectRegistry? This for example won't work for obvious reasons (changes in red):

import _winreg as winreg

SetRegistry('HKEY_LOCAL_MACHINE', key, values)

def SetRegistry(reg, key, values):
  reghandle = winreg.ConnectRegistry(None, winreg.reg)

Unfortunately, I can't use __str__(), since it's just an int:

>>> import _winreg
>>> print _winreg.HKEY_LOCAL_MACHINE
2147483650
>>> type(_winreg.HKEY_LOCAL_MACHINE)
<type 'long'>

Probably missing something simple ... :-/