Question: when were automatic weapons made illegal in the united states
[{'answer': 'June 26 , 1934', 'provenance': [{'wikipedia_id': '285219', 'title': 'National Firearms Act', 'start_paragraph_id': 1, 'start_character': 79, 'end_paragraph_id': 1, 'end_character': 93, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]