code: def columbus_day(year, country='usa'):
      '''in USA: 2nd Monday in Oct
         Elsewhere: Oct 12'''
      if country == 'usa':
          return nth_day_of_month(2, MON, OCT, year)
      else:
          return (year, OCT, 12f columbus_day(year, country='usa'):
      '''in USA: 2nd Monday in Oct
         Elsewhere: Oct 12'''
      if country == 'usa':
          return nth_day_of_month(2, MON, OCT, year)
      else:
          return (year, OCT, 12)
docs: in USA: 2nd Monday in Oct
         Elsewhere: Oct 12