Requires Jobs to have Diarization enabled

[bayu01]

Looks like https://docs.aws.amazon.com/transcribe/latest/dg/diarization.html is required. Code is looking to iterate over the speaker_labels key.

"speaker_labels": {
    "channel_label": "ch_0",
    "speakers": 2,
    "segments": [
         {

If the JSONs were produced without them code will fail with Error in
line 1491, in create_turn_by_turn_segments for segment in data["results"]["speaker_labels"]["segments"]: