How to use the juju.loop function in juju

def test_run_in_model(self):
        self.patch_object(model, 'Model')
        self.Model.return_value = self.Model_mock

        async def _wrapper():
            async with model.run_in_model('modelname') as mymodel:
                return mymodel
        self.assertEqual(loop.run(_wrapper()), self.Model_mock)
        self.Model_mock.connect_model.assert_called_once_with('modelname')
        self.Model_mock.disconnect.assert_called_once_with()

def test_run_in_model_exception(self):
        self.patch_object(model, 'Model')
        self.Model.return_value = self.Model_mock

        async def _wrapper():
            async with model.run_in_model('modelname'):
                raise Exception
        with self.assertRaises(Exception):
            loop.run(_wrapper())
        self.Model_mock.connect_model.assert_called_once_with('modelname')
        self.Model_mock.disconnect.assert_called_once_with()