Question: when was the first episode of south park released
[{'answer': 'August 13 , 1997', 'provenance': [{'wikipedia_id': '8233629', 'title': 'South Park (season 1)', 'start_paragraph_id': 21, 'start_character': 666, 'end_paragraph_id': 21, 'end_character': 682, 'bleu_score': 1.0, 'section': 'Section::::Development.\n'}]}]