year_first_day({date})
Accepts a DateTime, DateOnly, or legacy Date object as input. Returns an object of the same type that corresponds to the first day of the year that contains the specified date.
| date | year_first_day |
|---|---|
| 2015-01-21 15:30:00 | 2015-01-01 00:00:00 |
| 2015-01-21 00:00:00 | 2015-01-01 00:00:00 |
| 2015-01-31 10:00:30 | 2015-01-01 00:00:00 |
| 2015-02-03 15:30:00 | 2015-01-01 00:00:00 |
| 2016-01-21 23:59:59 | 2016-01-01 00:00:00 |
| 2015-10-31 23:59:59 | 2015-01-01 00:00:00 |
| 2015-12-03 00:00:00 | 2015-01-01 00:00:00 |
| 2016-01-11 03:30:00 | 2016-01-01 00:00:00 |
| 2016-01-11 03:30:00 | 2016-01-01 00:00:00 |