def get_urls(self):
        urls = super(VersionAdmin, self).get_urls()
        admin_site = self.admin_site
        opts = self.model._meta
        info = opts.app_label, opts.model_name,
        reversion_urls = [
                                  url("^recover/$", admin_site.admin_view(self.recoverlist_view), name='%s_%s_recoverlist' % info),
                                  url("^recover/(\d+)/$", admin_site.admin_view(self.recover_view), name='%s_%s_recover' % info),
                                  url("^([^/]+)/history/(\d+)/$", admin_site.admin_view(self.revision_view), name='%s_%s_revision' % info),]
        return reversion_urls + urls

    # Views.
Query the back-end EC2 services for instance details and return
dataset/ETHPy150Open etianen/django-reversion/src/reversion/admin.py/VersionAdmin.get_urls--crossover with--dataset/ETHPy150Open AppScale/appscale-tools/lib/agents/ec2_agent.py/EC2Agent.__describe_instances