Question: how long was law and order on the air
[{'answer': '20 seasons', 'provenance': [{'wikipedia_id': '173629', 'title': 'Law & Order', 'start_paragraph_id': 86, 'start_character': 175, 'end_paragraph_id': 86, 'end_character': 185, 'bleu_score': 1.0, 'section': 'Section::::Home media.\n'}]}]