how to make an error python code example

Example 1: throwing an exception python

raise Exception("message")

Example 2: python 3 except sys error info

1 import sys
   2 try:
   3   untrusted.execute()
   4 except: # catch *all* exceptions
   5   e = sys.exc_info()[0]
   6   write_to_page( "<p>Error: %s</p>" % e )