С помощью dateutil и calendar:
code
import calendar
from datetime import date
year = 2025
weekends = [date(year, m, d)
for m in range(1, 13)
for d in range(1, 32)
if calendar.monthrange(year, m)[1] >= d and calendar.weekday(year, m, d) >= 5]
print(weekends[:5])
Можно использовать для планирования.