def get_dir_from_zipfile(zip_file, fallback=None):
    """Return the name of the root folder in a zip file.

    :param zip_file: a :class:`zipfile.ZipFile` instance.
    :param fallback: if `None`, the name of the zip file is used. This is
        returned if the zip file contains more than one top-level directory,
        or none at all.
    """
    fallback = fallback or zip_file.filename
    directories = [name for name in zip_file.namelist() if name.endswith("/")
                   and len(PurePath(name).parts) == 1]
    return fallback if len(directories) > 1 else directories[0]
def test_user_login(self):
        c = Client()
        # User points the browser to the landing page
        res = c.post('/', follow=True)

        # the user is not logged in
        self.assertFalse(res.context['user'].is_authenticated)
        # and is redirected to the login page
        self.assertRedirects(res, '/login/')

        # The login page is being rendered by the correct template
        self.assertTemplateUsed(res, 'registration/login.html')

        # asks the user to login using a set of valid credentials
        res = c.post('/login/', data=self.credentials, follow=True)

        # The system acknowledges him
        self.assertTrue(res.context['user'].is_authenticated)

        # and moves him at the dashboard
        self.assertTemplateUsed(res, 'app/dashboard.html')