fixing KeyError in show_navigation when deleting objects from nexus admin
fixing KeyError in show_navigation when deleting objects from nexus admin

brilliant-org/nexus,YPlan/nexus,roverdotcom/nexus,roverdotcom/nexus,disqus/nexus,blueprinthealth/nexus,Raekkeri/nexus,graingert/nexus,brilliant-org/nexus,disqus/nexus,Raekkeri/nexus,brilliant-org/nexus,YPlan/nexus,blueprinthealth/nexus,graingert/nexus,graingert/nexus,disqus/nexus,blueprinthealth/nexus,YPlan/nexus,roverdotcom/nexus