document:
  nodes:
    - object: block
      type: paragraph
      nodes:
        - object: text
          leaves:
            - text: Hello world
    - object: block
      type: x-import
      isVoid: true
      data:
        '0': hello.md
    - object: block
      type: paragraph
      nodes:
        - object: text
          leaves:
            - text: After the import