def get_date_created(self, obj): return dt_to_unix(obj.date_created)
def get_date_opened(self, obj): return dt_to_unix(obj.date_opened) if obj.date_opened else None
def get_date_closed(self, obj): return dt_to_unix(obj.date_closes) if obj.date_closes else None
def get_date_published(self, obj): return dt_to_unix(obj.date_published) if obj.date_published else None