code: def gregorian_date(year, julian_day):
  	
  	result = datetime.date(year, 1, 1)
  	result += datetime.timedelta(days=julian_day - 1)
  	return result
docs: Gregorian Date is defined as a year and a julian day (1-based
  	index into the days of the year).
  
  	>>> gregorian_date(2007, 15)
  	datetime.date(2007, 1, 15)