Custom Post Annotation Lambda Function for Custom Labeling Job

Hello,

I have implemented a post annotation lambda function for my sagemaker ground truth custom job.

After the annotations are finished, the results come after the consolidation of the annotations are saved in a subdirectory called "iteration_X" of "annotations/consolidated-annotation/consolidation-response/".

However, the outcome of the annotations is never successful and from the log of the lambda function used for the post annotation I always receive this type of error:

{
    "labeling-job-name": "labeling-job-full-dataset-test-giusy-10",
    "event-name": "ANNOTATION_CONSOLIDATION_LAMBDA_SCHEMA_MATCHING_FAILED",
    "event-log-message": "ERROR: Annotation consolidation Lambda response did not match expected data format for line 1."
}

Based on this guide (https://docs.aws.amazon.com/id_id/sagemaker/latest/dg/sms-custom-templates-step3-lambda-requirements.html) I made sure that my lambda function returns:

RESPONSE:

[
  {
    "datasetObjectId": "1",
    "consolidatedAnnotation": {
      "content": {
        "annotations": {
          "relations": [
            {
              "subj": "CW",
              "predicate": "adjust",
              "obj": "key"
            },
            {
              "subj": "key",
              "predicate": "with",
              "obj": "right_hand"
            },
            {
              "subj": "key",
              "predicate": "on",
              "obj": "lock"
            }
          ],
          "groundings": {
            "pre_frame": [
              {
                "object": "right_hand",
                "left": 776.5,
                "top": 219.5,
                "width": 282.52,
                "height": 246.5
              },
              {
                "object": "lock",
                "left": 716.4,
                "top": 255.6,
                "width": 93.60000000000002,
                "height": 111.6
              }
            ],
            "pnr_frame": [
              {
                "object": "right_hand",
                "left": 974.16,
                "top": 275.14,
                "width": 287.21,
                "height": 215.84
              },
              {
                "object": "lock",
                "left": 914.4,
                "top": 291.6,
                "width": 97.20000000000005,
                "height": 90
              }
            ],
            "post_frame": [
              {
                "object": "right_hand",
                "left": 858.58,
                "top": 240.54,
                "width": 316.28,
                "height": 209.37
              },
              {
                "object": "lock",
                "left": 741.6,
                "top": 237.6,
                "width": 61.19999999999993,
                "height": 169.20000000000002
              }
            ]
          },
          "timestamp": "0",
          "clip_uid": "undefined"
        }
      }
    }
  }
]

I can't figure out how to avoid this type of error and make the annotations go through when the job is finished.