Python TZ Aware datetime and DST Conversion Example

example.py

import datetime
import pytz

tz_ny = pytz.timezone('America/New_York')

dt_aware_dst_active = tz_ny.localize(datetime.datetime(2023, 5, 1, 12, 0))
dt_aware_dst_inactive = tz_ny.localize(datetime.datetime(2023, 12, 1, 12, 0))

print("Original DST Active Offset (America/New_York):", dt_aware_dst_active.dst())
print("Original DST Active (America/New_York):", dt_aware_dst_active)
print("To UTC, DST Active (America/New_York):", dt_aware_dst_active.astimezone(pytz.utc))
print("Roundtrip, DST Active (America/New_York):", dt_aware_dst_active.astimezone(pytz.utc).astimezone(tz_ny))
print()
print("Original DST Inactive Offset (America/New_York):", dt_aware_dst_inactive.dst())
print("Original DST Inactive (America/New_York):", dt_aware_dst_inactive)
print("To UTC, DST Inactive (America/New_York):", dt_aware_dst_inactive.astimezone(pytz.utc))
print("Roundtrip, DST Inactive (America/New_York):", dt_aware_dst_inactive.astimezone(pytz.utc).astimezone(tz_ny))

Output:

Original DST Active Offset (America/New_York): 1:00:00
Original DST Active (America/New_York): 2023-05-01 12:00:00-04:00
To UTC, DST Active (America/New_York): 2023-05-01 16:00:00+00:00
Roundtrip, DST Active (America/New_York): 2023-05-01 12:00:00-04:00

Original DST Inactive Offset (America/New_York): 0:00:00
Original DST Inactive (America/New_York): 2023-12-01 12:00:00-05:00
To UTC, DST Inactive (America/New_York): 2023-12-01 17:00:00+00:00
Roundtrip, DST Inactive (America/New_York): 2023-12-01 12:00:00-05:00