default set to boolean False and help set to string 'Tells Django to stop running the test suite after first failed test.'. call the method parser.add_argument with 4 arguments: string '--testrunner', action set to string 'store', dest set to 'testrunner',
parser . add_argument ( '--testrunner' , action = 'store' , dest = 'testrunner' , help = 'Tells Django to use specified test runner class instead of ' 'the one specified by the TEST_RUNNER setting.' ) ,