code: def clear_published(self):
          
          metadata = Metadata(**settings.METADATA['published'])
          if metadata.is_read_only() or metadata.is_required():
              raise NoAccess()
          self._my_map['published'] = False
docs: Removes the published status.
  
          :raise: ``NoAccess`` -- ``Metadata.isRequired()`` is ``true`` or ``Metadata.isReadOnly()`` is ``true``
  
          *compliance: mandatory -- This method must be implemented.*