{
  "uniqueFields": ["foo", "foo[]", "foo[].bar", "foo[].bar.baz", "notes"],
  "headerFields": ["foo", "foo[0]", "foo[1].bar", "foo[2].bar.baz", "notes"],
  "preview": [
    ["1", "", "", "", "simple value"],
    ["", "1", "", "", "single element array"],
    [
      "",
      "1",
      "1",
      "1",
      "three element array where first value is simple; second value is object with one field; third value is object with object with one field"
    ]
  ]
}