```
AttributeError: module 'posthog.queries.sessions' has no attribute 'Sessions'
(6 additional frame(s) were not displayed)
...
  File "posthog/api/dashboard.py", line 101, in get_items
    update_dashboard_items_cache(dashboard)
  File "posthog/tasks/update_cache.py", line 73, in update_dashboard_items_cache
    update_cache_item(cache_key, cache_type, payload)
  File "posthog/tasks/update_cache.py", line 64, in update_cache_item
    result = _calculate_by_filter(filter, key, team_id, cache_type)
  File "posthog/tasks/update_cache.py", line 144, in _calculate_by_filter
    insight_class = import_from(insight_class_path[0], insight_class_path[1])
  File "posthog/tasks/update_cache.py", line 132, in import_from
    return getattr(importlib.import_module(module), name)
```
posthog/api/test/test_dashboard.py
dashboard = Dashboard.objects.create(team=self.team, name="dashboard")
        filter_dict = {
            "events": [{"id": "$pageview"}],
            "properties": [{"key": "$browser", "value": "Mac OS X"}],
        }
        with freeze_time("2020-01-04T13:00:01Z"):
            
            item = DashboardItem.objects.create(
                dashboard=dashboard, filters=Filter(data=filter_dict).to_dict(), team=self.team, last_refresh=now()
            )
        with freeze_time("2020-01-20T13:00:01Z"):
            response = self.client.get("/api/dashboard/%s?refresh=true" % dashboard.pk).json()
            self.assertIsNotNone(response["items"][0]["result"])
            self.assertIsNotNone(response["items"][0]["last_refresh"])
            self.assertEqual(response["items"][0]["result"][0]["count"], 0)
            item = DashboardItem.objects.get(pk=item.pk)
            self.assertAlmostEqual(item.last_refresh, now(), delta=timezone.timedelta(seconds=5))
    def test_dashboard_endpoints(self):