callling dynamically obtained win32api function

[Nospam]

I'm trying to understanding how to complete this following code:

import os
import win32api

GWL_EXSTYLE=-20
LWA_ALPHA=0x2

u32=win32api.LoadLibrary("user32.dll")
if u32:
     slwa=win32api.GetProcAddress(u32, "SetLayeredWindowAttributes");
     print type(slwa)
     # how do I call slwa here? I tried win32api.Apply ...
     win32api.FreeLibrary(u32)

I could not find an example of doing this in the docs.

Thanks