Question: when did child labor end in the us
[{'answer': '1938', 'provenance': [{'wikipedia_id': '433010', 'title': 'Child labor laws in the United States', 'start_paragraph_id': 13, 'start_character': 130, 'end_paragraph_id': 13, 'end_character': 134, 'bleu_score': 1.0, 'section': 'Section::::Activism against child labor.\n'}]}, {'provenance': [{'wikipedia_id': '433010', 'title': 'Child labor laws in the United States', 'start_paragraph_id': 13, 'start_character': 0, 'end_paragraph_id': 13, 'end_character': 338, 'bleu_score': 0.965203995518735, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3819764160033363969}, 'section': 'Section::::Activism against child labor.\n'}]}]