hmm this looks like a copy paste issue to me. I don't get any unexpected token errors when I manually type in whats in your screenshot
Lot-->
set(material.shader, "/Material_test/Content/Megascans/Surfaces/Brick_Wall_wmknbhe/MI_Brick_Wall_wmknbhe_2K.uasset")
Did you copy it directly from the blog post? I remember having the same issue in the past that when copying CGA snippets from the blog that sometimes it copies some hidden char, which can't be handled by the CGA compiler.
I suggest to try it with a new file and manually typing it in or copy to notepad first.