Invoke parse_data_to_internal() for every element
        in self.data

def parse_data_to_internal(self, include_custom=False):
        """
        Invoke parse_data_to_internal() for every element
        in self.data
        """
        for element in self.data:
            self.data[element].parse_data_to_internal()
        if include_custom:
            for element in self.custom_data:
                self.custom_data[element].parse_data_to_internal()