Question: when was china's one child policy enacted
[{'answer': '1979', 'provenance': [{'wikipedia_id': '44664', 'title': 'One-child policy', 'start_paragraph_id': 1, 'start_character': 418, 'end_paragraph_id': 1, 'end_character': 422, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '44664', 'title': 'One-child policy', 'start_paragraph_id': 1, 'start_character': 373, 'end_paragraph_id': 1, 'end_character': 900, 'bleu_score': 0.516662313148031, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3157298011949496670}, 'section': 'Section::::Abstract.'}]}]