def METHOD_NAME(self, builder):
    """Return True if this builder has been written to (or read from) disk by this IO object, False otherwise.
    :param builder: Builder object to get the written flag for
    :type builder: Builder
    :return: True if the builder is found in self._written_builders using the builder ID, False otherwise
    """
    builder_id = self.__builderhash(builder)
    return self.get(builder_id, False)