抛出异常

by raise statement, for example:

#! /usr/bin/python

import sys,os

try:
    f = open('myfile.txt')
    s = f.readline()
    i = int(s.strip())
except IOError, (errno,strerror):
    print "I/O error(%s): %s" %(errno,strerror)
except ValueError:
    print "Could not convert data to an integer"
except:
    print "Unexpected error:", sys.exec_info()[0]
    raise

raise NameError, "Just for test! "

Get the result as blow:

D:\SVNtest>python test.py
Traceback (most recent call last):
  File "test.py", line 17, in <module>
    raise NameError, "Just for test! "
NameError: Just for test!