From what I can see from your image (it might be helpful to post / attach the script code also to your posting, this makes it easier to copy / paste it in an editor for us), you might have an issue using a double quote instead of a single quote in line 6.
Then, your load statement is of course not complete yet, you need to define the source and you'll need to use a group by clause when using aggregation functions like concat in your load.
The script editor sometimes marks parts of the script as error (red underline), though the syntax is correct and the script works. It seems to do so in your first concat() function, claiming the concatenated delimiter string as error (I think it is correct, though).
I am not 100% sure about what this snippet should do in a more gobal context of the wildcard mapping, I assume that you will create some more code after this load to do the actual mapping, right?