@abc.abstractmethod<EOL><INDENT>def set_value_heading_type(self, heading_type):<DEDENT>
pass<EOL>
Sets a heading type.

        :param heading_type: the new heading type
        :type heading_type: ``osid.type.Type``
        :raise: ``InvalidArgument`` -- ``heading_type`` is invalid
        :raise: ``NoAccess`` -- ``Metadata.isReadOnly()`` is ``true``
        :raise: ``NullArgument`` -- ``heading_type`` is ``null``

        *compliance: mandatory -- This method must be implemented.*