Question: when was the first sonic drive in opened
[{'answer': '1956', 'provenance': [{'wikipedia_id': '305493', 'title': 'Sonic Drive-In', 'start_paragraph_id': 9, 'start_character': 812, 'end_paragraph_id': 9, 'end_character': 816, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '305493', 'title': 'Sonic Drive-In', 'start_paragraph_id': 9, 'start_character': 0, 'end_paragraph_id': 9, 'end_character': 920, 'bleu_score': 0.9871375943883031, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 18262134057467876751}, 'section': 'Section::::History.\n'}]}]