docs: def child_(self, ctx):
          """
          If the root resource is requested, return the primary
          application's front page, if a primary application has been
          chosen.  Otherwise return 'self', since this page can render a
          simple index.
          """
          if self.frontPageItem.defaultApplication is None:
              return self.webViewer.wrapModel(
                  _OfferingsFragment(self.frontPageItem))
          else:
              return SharingIndex(self.frontPageItem.defaultApplication.open(),
                                  self.webViewer).locateChild(ctx, [''])[0]