How to sort result based on one item's data

[blockhunts]

I want to insert a sort function inside the converter based on category.
I tried to define the sort code as seen below, but it doesn't work.

dataConvert = (
       c.chunk_by(c.item("Category")) #Group the category consecutively 
       .aggregate(
           {
           "Category": c.ReduceFuncs.First(c.this).item("Category"),
               "CategoryName": c.ReduceFuncs.First(c.this).item("CategoryName"),
               }
       ) # Aggregate the items per occuring category, not yet grouped per unique category
       .sort(key=lambda item: item,)
       .pipe(
       c.group_by(c.item("Category"), c.item("カテゴリコメント")).aggregate(  # type: ignore
               {
                   "Category": c.item("Category"),
                   "CategoryName": c.item("CategoryName"),
                   }
           )
       ) # Group all the items per unique category
       .gen_converter()
       )

[blockhunts]

Change this code from this:

.sort(key=lambda item: item)

to this:

.sort(key=lambda item: item["Category"])

Credits to @westandskif