Question: when does season 18 of law and order svu start
[{'answer': 'September 21 , 2016', 'provenance': [{'wikipedia_id': '49294805', 'title': 'Law & Order: Special Victims Unit (season 18)', 'start_paragraph_id': 1, 'start_character': 50, 'end_paragraph_id': 1, 'end_character': 69, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Wednesday , September 21 , 2016'}, {'provenance': [{'wikipedia_id': '49294805', 'title': 'Law & Order: Special Victims Unit (season 18)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 147, 'bleu_score': 0.718046308632153, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14191089881671316262}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '49294805', 'title': 'Law & Order: Special Victims Unit (season 18)', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['The eighteenth season of "" debuted on Wednesday, September 21, 2016, on NBC and finished on Wednesday, May 24, 2017, with a two-hour season finale.', 'The eighteenth season of "" debuted on Wednesday, September 21, 2016', 'The eighteenth season of "" debuted on Wednesday, September 21, 2016, on NBC and finished on Wednesday, May 24, 2017, with a two-hour season finale.']}}]}]