## Is your feature request related to a problem?

There's only 2 files where we use pandas, but pandas is 49MB and numpy is another 86MB, slowing down builds massively.

## Describe the solution you'd like

Replace pandas with a pure SQL/Python solution in
- posthog/queries/trends.py
- posthog/queries/sessions.py

Both of those have equivalent examples in Clickhouse (ee/clickhouse) that don't use Pandas.

## Describe alternatives you've considered

Continue using Pandas and clogging builds

## Additional context



#### *Thank you* for your feature request – we love each and every one!

posthog/queries/test/test_trends.py
event_factory(
                    team=self.team,
                    event="sign up",
                    distinct_id="blabla",
                    properties={"$some_property": "value", "$browser": "Safari"},
                )
            with freeze_time("2020-01-02 00:06:34"):
                event_factory(
                    team=self.team,
                    event="sign up",
                    distinct_id="blabla",
                    properties={"$some_property": "value", "$browser": "Safari"},
                )
                event_factory(
                    team=self.team,
                    event="sign up",
                    distinct_id="blabla",
                    properties={"$some_property": "value", "$browser": "Safari"},
                )
            with freeze_time("2020-01-04T13:00:01Z"):
                daily_response = trends().run(
                    Filter(data={"display": TRENDS_TABLE, "breakdown": "$browser", "events": [{"id": "sign up"}],}),
                    self.team,
                )
            for result in daily_response:
                if result["breakdown_value"] == "Chrome":
                    self.assertEqual(result["aggregated_value"], 2)
                else:
                    self.assertEqual(result["aggregated_value"], 5)
        def test_trends_breakdown_single_aggregate_math(self):