'Verifies the basic behavior of delete_user_preference.'

def test_delete_user_preference(self):

    self.assertTrue(delete_user_preference(self.user, self.test_preference_key))
    set_user_preference(self.user, self.test_preference_key, self.test_preference_value)
    self.assertTrue(delete_user_preference(self.user, self.test_preference_key, username=self.user.username))
    self.assertFalse(delete_user_preference(self.user, 'no_such_key'))
