{% host_url %} in django tests raises error django.urls.exceptions.NoReverseMatch

[XJOJIX]

is there a way to work with host_url tags in tests?

template:

{% load hosts %}
{% host_url 'www:index' host 'www' %}

error:

django.urls.exceptions.NoReverseMatch: 'www' is not a registered namespace

test:

@override_settings(DEFAULT_HOST='sub_domain', ROOT_URLCONF='sub_domain.urls')
class IndexViewTest(TestCase):
    def setUp(self):
        self.client = Client()
        self.url = reverse_lazy('index')

    def test_index_get(self):
        response = self.client.get(self.url)
        self.assertEqual(response.status_code, 200)