Question: when did the use of lead paint end
[{'answer': '1978', 'provenance': [{'wikipedia_id': '23034778', 'title': 'Lead-based paint in the United States', 'start_paragraph_id': 1, 'start_character': 152, 'end_paragraph_id': 1, 'end_character': 156, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '23034778', 'title': 'Lead-based paint in the United States', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 334, 'bleu_score': 0.8700465171198001, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14093098914111255021}, 'section': 'Section::::Abstract.'}]}]