@abc.abstractmethod<EOL><INDENT>def has_relative_weekday_end_offset(self):<DEDENT>
return<EOL>
Tests if this ending time offset is a based on a relative weekday.

        :return: ``true`` if this offset is based on a relative weekday, ``false`` otherwise
        :rtype: ``boolean``
        :raise: ``IllegalState`` -- ``has_fixed_end_offset()`` is ``true``

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