add further eplaination
@@ -102,7 +102,12 @@ def _sort_contour_sequences(dicom_json_dataset):
def _dict_sorting(d):
"""A dictionary sorting key to be utilised on a DICOM JSON representation
- of a Contour Sequence Item"""
+ of a Contour Sequence Item
+
+ It sorts first by the SOP Instance UID, and then if that is equal
+ it sorts by the length of the contour data itself. If that's equal
+ then it is random, but that isn't an issue for this current test
+ case."""
CONTOUR_IMAGE_SEQUENCE_TAG = "30060016"
REFERENCED_SOP_INSTANCE_UID_TAG = "00081155"
