fixed text and source for excel

handout/sections/3d-excel.typ

@@ -37,9 +37,7 @@
     columns: (50%,50%),
     inset: 0pt, column-gutter: 0.3cm, stroke: none,
     align: horizon,
-
-    sourcecode(lang: "Python", raw( read("../code/3d/output2excel-snippet.py") )),
-
+    pysrc_with_ok("3d/output2excel-snippet.py"),
     box( stroke: 0pt + gray,
       align(center, [
         Ansicht in MS Excel: