def METHOD_NAME(db, client, username, password):
    client.login(username=username, password=password)
    instances = Task.objects.all()
    for instance in instances:
        url = reverse(urlnames['detail_export'], args=[instance.pk])
        response = client.get(url)
        assert response.status_code == status_map['list'][username], response.content
        if response.status_code == 200:
            root = et.fromstring(response.content)
            assert root.tag == 'rdmo'
            for child in root:
                assert child.tag in ['task']