def S3MarkerAclFromObjectMetadata(object_metadata):
  if (object_metadata and object_metadata.metadata and
      object_metadata.metadata.additionalProperties):
    for prop in object_metadata.metadata.additionalProperties:
      if prop.key == S3_ACL_MARKER_GUID:
        return prop.value
Retrieves GUID-marked S3 ACL from object metadata, if present.
dataset/ETHPy150Open GoogleCloudPlatform/gsutil/gslib/translation_helper.py/S3MarkerAclFromObjectMetadata