CONTRIBUTING.md: fix bug in file_prefix definition

1db31f43 · Laurent Modolo · 11121155 · 1db31f43
Verified Commit 1db31f43 authored 3 years ago by Laurent Modolo
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -139,7 +139,7 @@ If you want to use information within the `file_id` to name outputs in your `scr
      file_prefix = file_id.values()[0]
    break
    default:
-      file_id
+      file_prefix = file_id
    break
  }
 ```