Expecting a test to fail in Python or Django

How do you expect a test to fail when using Python or Django

You need to make use of assertRaises

We need to ensure we use the context keyword with

To expect a KeyError:

    def test_init_without_entry(self):
        with self.assertRaises(KeyError):
            CommentForm()

To expect a TypeError:

    def test_split(self):
        s = 'hello world'
        # check that s.split fails when the separator is not a string
        with self.assertRaises(TypeError):
            s.split(2)

Source: assertRaises