def check_variants(self, impl, arg_gen, **kwargs):
        """Run self.check(impl, ...) on array data generated from arg_gen.
        """
        for args in arg_gen():
            with self.subTest(list(map(typeof, args))):
                self.check(impl, *args, **kwargs)
Run self.check(impl, ...) on array data generated from arg_gen.
        
numba/tests/test_parfors.py