document:
  nodes:
    # orphan item
    - object: block
      type: list_item
      nodes:
        - object: block
          type: paragraph
          nodes:
            - object: text
              leaves:
                - text: "Orphan"

    - object: block
      type: ul_list
      nodes:
        - object: block
          type: list_item
          nodes:
            - object: block
              type: paragraph
              nodes:
                - object: text
                  leaves:
                    - text: "Valid item"
        # Item that contains another item
        - object: block
          type: list_item
          nodes:
            - object: block
              type: list_item
              nodes:
                - object: block
                  type: paragraph
                  nodes:
                    - object: text
                      leaves:
                        - text: "Direct child of another item"