A function groups commands under a name. Defining it doesn't execute its body.
Arguments supplied when calling the function become its positional parameters, so a reusable printer should read its own first argument. Keep the body and the call visible in the saved script. A helper that merely prints one hard-coded route is less useful for the next batch.
These tasks ask for a small function whose result can be inspected independently. Call route east to give route its own first argument. A local variable declared inside the function can hold temporary work without replacing the caller's value. The function's final command supplies its status unless return sets one explicitly. Check that status when later commands depend on the helper completing successfully.