def METHOD_NAME(self):
    link_cols = list(self.links_df.columns)
    link_req = [k for k in self.gmns_links["fields"] if self.gmns_links["fields"][k]["required"]]
    main_cols = ["link_id", "from_node_id", "to_node_id", "directed"]
    link_cols = (
        main_cols
        + [c for c in link_cols if c in link_req and c not in main_cols]
        + [c for c in link_cols if c not in link_req]
    )
    node_cols = list(self.nodes_df.columns)
    node_req = [k for k in self.gmns_nodes["fields"] if self.gmns_nodes["fields"][k]["required"]]
    main_cols = ["node_id", "x_coord", "y_coord"]
    node_cols = (
        main_cols
        + [c for c in node_cols if c in node_req and c not in main_cols]
        + [c for c in node_cols if c not in node_req]
    )
    self.links_df = self.links_df[link_cols]
    self.nodes_df = self.nodes_df[node_cols]