def addError(self, test, err):
        TestResult.addError(self, test, err)
        if err[0] is KeyboardInterrupt:
            self.shouldStop = 1
        self._lastWas = 'error'
        self._errorsAndFailures += err[0] % '<error type="%s">'
        for line in apply(traceback.format_exception, err):
           for l in string.split(line,"\n")[:-1]:
              self._errorsAndFailures += "%s" % l
        self._errorsAndFailures += "</error>"
dataset/ETHPy150Open garethr/django-test-extensions/src/test_extensions/testrunners/xmlunit/unittest.py/_XmlTextTestResult.addError/swapped operands of `%`