Question: when did grey's anatomy start this season
[{'answer': 'September 28 , 2017'}, {'provenance': [{'wikipedia_id': '1660277', 'title': "Grey's Anatomy", 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 295, 'bleu_score': 0.6498946080872731, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17046586206913855901}, 'section': 'Section::::Abstract.'}]}]