def create_post(self, group, params):
     category_ids = set([str(x[0]) for x in self.db.session.query(Category.id).order_by(Category.id).all()])
     if not category_ids.issubset(params.keys()):
         return self.create_get("Please select a winner for every category")
     if params["selection_name"] == "":
         return self.create_get("Please select a name for your selections")
     selection = Selection(params["selection_name"])
     selection.group_id = group.id
     self.db.session.add(selection)
     self.db.session.commit()
     picks = list()
     for category_id in category_ids:
         nominee_id = int(params[category_id])
         pick = Pick(selection.id, category_id, nominee_id)
         picks.append(pick)
     self.db.session.add_all(picks)
     self.db.session.commit()
     return self.get(group=group, selection_id=selection.id)