from _winreg import *
key = CreateKey(HKEY_CURRENT_USER, "TestKey")
try:
	SetValueEx(key, "expandKey", 0, REG_EXPAND_SZ, "%programfiles%")
	print EnumValue(key, 0) #('expandKey', 'C:\\Program Files', 2)
finally:
	DeleteKey(HKEY_CURRENT_USER, "TestKey")