{
  "testcases": {
    "sandbox": {
      "action": "gfpoly_diff",
      "arguments": {
        "F": [
          "IJustWannaTellYouAAAAA==",
          "HowImFeelingAAAAAAAAAA==",
          "GottaMakeYouAAAAAAAAAA==",
          "UnderstaaaaaaaaaaaaanQ=="
        ]
      }
    }
  }
}