Returns calendar facts for a date: the day of the week, ISO weekday number (1=Monday), whether it falls on a weekend, the ISO week number and week-year, the day of the year, and the calendar quarter.
Accepts YYYY-MM-DD or ISO 8601; defaults to today. Public-holiday awareness lives in the business_days tool and the holidays namespace. Computed locally.
Date or datetime (YYYY-MM-DD or ISO 8601). Defaults to today.