blob: ef3a52d9ba99fedd30f1ecfbedc273ad35012759 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
|
from collections import defaultdict
from typing import Any
def group_by_year(records: list[dict], datetime_field: str) -> dict[int, list[Any]]:
"""Memory efficient - processes records one at a time"""
by_year = defaultdict(list)
for record in records:
# Extract year from ISO string without full datetime parsing
year = int(record[datetime_field][:4])
by_year[year].append(record)
return dict(by_year)
|
