def code(self,status):
        try:
            tc.go(self.url)
            tc.code(status)
        except TwillAssertionError:
            self.fail("%s did not return a %s" % (self.url, status))
By default Twill commands throw exceptions rather than failures when 
dataset/ETHPy150Open garethr/django-test-extensions/src/test_extensions/twill.py/TwillCommon.code