How to use the chemin.Chemin.create function in chemin

.map((childRoute): Route | null => {
          const middlewares = [...parentMiddleware, ...childRoute.middleware];
          const patterns = [route.pattern, childRoute.pattern];
          if (childRoute.pattern && route.exact) {
            console.warn(
              `Error: ${route.pattern} is expected to be exact but its children ${childRoute.pattern} has a pattern, the child pattern will be ignored`
            );
            patterns[1] = null;
          }
          const pattern = Chemin.create(...patterns.filter(Chemin.isChemin));
          const exact = route.exact || childRoute.exact;
          const method = combineMethods(route.method, childRoute.method, m => {
            console.warn(
              `Error: in ${route.pattern} > ${route.pattern} the Method ${m} is not allowed by parent. It will be ignored !`
            );
          });
          return createRoute({ pattern, exact, method }, middlewares, childRoute.children);
        })
        .filter((r: Route | null): r is Route => r !== null)