Pyhon script error 8007007e

I runned a very simple test python script,then it cat an error:
Error:80040154, CoCreateInstance() for PYTHONSCRIPT

My operating envoirment is windows 7 64bits.

python:Python 2.7.14 (v2.7.14:84471935ed, Sep 16 2017, 20:19:30) [MSC v.1500 32 bit (Intel)] on win32

and i had Registered: Python.

The script is:
def Main():
xsh.Screen.Send('test')

Program Ver. : Xshell 5