Hi team! I think I may have found a bug or improvement for flow deployments. When defining a schedule, one of the options is using the RRule as per https://docs.prefect.io/api-ref/server/schemas/schedules/#prefect.server.schemas.schedules.RRuleSchedule However, this doesn’t appear compatible with python’s ZoneInfo way of defining timezones:

from zoneinfo import ZoneInfo
from dateutil.rrule import MINUTELY, rrule
from prefect import flow
from prefect.deployments import Deployment
from prefect.server.schemas.schedules import RRuleSchedule

london = ZoneInfo("Europe/London")

@flow
def some_flow():
    print("whoa")

Deployment.build_from_flow(
    flow=some_flow, 
    schedule=RRuleSchedule.from_rrule(
        rrule(
            freq=MINUTELY,
            interval=10,
            dtstart=dt(2020, 1, 1, tzinfo=london),
            byhour=range(8, 9),
        )
    ),
)

Naively, I’d expect this to work, but it fails because ZoneInfo doesnt have a name attribute

schedule=RRuleSchedule.from_rrule(
  File "/Users/sh/Projects/flows/.venv/lib/python3.9/site-packages/prefect/server/schemas/schedules.py", line 410, in from_rrule
    timezone = rrule._dtstart.tzinfo.name
AttributeError: 'zoneinfo.ZoneInfo' object has no attribute 'name'

Theres an easy workaround here (like setting the timezone name explicitly like is done in schedules.py:413, but thought it might be good to get this working with pythons new standard way of handling timezones, especially because the old

from datetime import timezone

requires specifying an hour delta which actually doesnt get used by prefect2