python3.9在调用c.dll时出问题

import os
import ctypes
os.add_dll_directory('C:\Users\adadxxx0\Desktop\python')
ctypes.cdll.LoadLibrary('./kmclassdll.dll')

报错提示:
Could not find module ‘C:Usersadadxxx0Desktoppythonkmclassdll.dll’ (or one of its dependencies). Try using the full path with constructor syntax.
File “C:Usersadadxxx0Desktoppython1.py”, line 4, in
ctypes.cdll.LoadLibrary(‘./kmclassdll.dll’)