zoneinfo Module¶
The zoneinfo module provides IANA time zone support for accurate timezone handling, including daylight saving time.
Complexity Reference¶
| Operation | Time | Space | Notes |
|---|---|---|---|
ZoneInfo() |
O(n) | O(n) | n = tzdata size; cached after first load |
| Convert timezone | O(log t) | O(1) | t = transitions in zone |
Working with Time Zones¶
Using Timezones¶
from zoneinfo import ZoneInfo
from datetime import datetime
# Create timezone - O(n) on first load
est = ZoneInfo("America/New_York")
pst = ZoneInfo("America/Los_Angeles")
# Create datetime with timezone - O(1)
dt = datetime(2024, 1, 15, 12, 0, tzinfo=est)
print(dt) # 2024-01-15 12:00:00-05:00
# Convert timezone - O(log t)
dt_pst = dt.astimezone(pst)
print(dt_pst) # 2024-01-15 09:00:00-08:00
# Get timezone name - O(1)
print(dt.tzname()) # EST