Question: when did grocery stores start using plastic bags
[{'answer': '1982', 'provenance': [{'wikipedia_id': '1613869', 'title': 'Plastic shopping bag', 'start_paragraph_id': 6, 'start_character': 498, 'end_paragraph_id': 6, 'end_character': 502, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '1613869', 'title': 'Plastic shopping bag', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 547, 'bleu_score': 0.978138775770484, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1350343875268217664}, 'section': 'Section::::History.\n'}]}]