item-0 at level 0: unspecified: group _root_
  item-1 at level 1: title: Introduction
    item-2 at level 2: text: This is the first paragraph of the introduction.
    item-3 at level 2: section_header: Background
      item-4 at level 3: text: Some background information here.
      item-5 at level 3: picture
      item-6 at level 3: list: group list
        item-7 at level 4: list_item: First item in unordered list
        item-8 at level 4: list_item: Second item in unordered list
      item-9 at level 3: list: group ordered list
        item-10 at level 4: list_item: First item in ordered list
        item-11 at level 4: list_item: Second item in ordered list
      item-12 at level 3: list: group ordered list start 42
        item-13 at level 4: list_item: First item in ordered list with start
        item-14 at level 4: list_item: Second item in ordered list with start