Remove data of type foramt.

        If type argument is omitted, remove all data.

def clearData(self, type: str = '') -> None:
        """Remove data of type foramt.

        If type argument is omitted, remove all data.
        """
        type = normalize_type(type)
        if not type:
            self.__data.clear()
        elif type in self.__data:
            del self.__data[type]