new_contents: class Jalaali:
      @staticmethod
      def to_jalaali(gy, gm, gd):
          """Convert a Gregorian date to Jalaali
  
          :param gy: Gregorian Year
          :type gy: int
          :param gm: Gregorian Month
          :type gm: int
          :param gd: Gregorian Day
          :type gd: int
          :return: the converted Jalaali date
          :rtype: tuple
          """
          # TODO return method to_jalaali
  
      @staticmethod
      def to_gregorian(jy, jm, jd):
          """Convert a Jalaali date to Gregorian
  
          :param jy: Jalaali Year
          :type jy: int
          :param jm: Jalaali Moth
          :type jm: int
          :param jd: Jalaali Day
          :type jd: int
          :return: the converted Gregorian date
          :rtype: tuple
          """
  
          # TODO return method to_Gregorian
  
      @staticmethod
      def is_valid_jalaali_date(jy, jm, jd):
          """Checks whether a Jalaali date is valid or not.
  
          :param jy: Jalaali Year
          :type jy: int
          :param jm: Jalaali Month
          :type jm: int
          :param jd: Jalaali Day
          :type jd: int
          :return: is date valid?
          :rtype: bool
          """
          year_is_valid = (-61 <= jy <= 3177)
          month_is_valid = (1 <= jm <= 12)
          pass
  
      @staticmethod
      def is_leap_jalaali_year(jy):
          """Checks whether this is a leap year or not.
  
          :param jy: Jalaali Year
          :type jy: int
          :return: is leap year?
          :rtype: bool
          """
          pass
  
subject: create jalaali.py and add some methos.