code: def hdate_to_jdn(date):
      
      day = date.day
      month = date.month
      if date.month == 13:
          month = 6
      if date.month == 14:
          month = 6
          day += 30
  
      # Calculate days since 1,1,3744
      day = _days_from_3744(date.year) + (59 * (month - 1) + 1) // 2 + day
  
      # length of year
      length_of_year = get_size_of_hebrew_year(date.year)
      # Special cases for this year
      if length_of_year % 10 > 4 and month > 2:  # long Heshvan
          day += 1
      if length_of_year % 10 < 4 and month > 3:  # short Kislev
          day -= 1
      if length_of_year > 365 and month > 6:  # leap year
          day += 30
  
      # adjust to julian
      return day + 1715118
docs: Compute Julian day from Hebrew day, month and year.
  
      Return: julian day number,
              1 of tishrey julians,
              1 of tishrey julians next year