Question: who prepared the first draught constitution of india
[{'answer': 'Benegal Narsing Rau', 'provenance': [{'wikipedia_id': '20234656', 'title': 'B. N. Rau', 'start_paragraph_id': 1, 'start_character': 4, 'end_paragraph_id': 1, 'end_character': 23, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '20234656', 'title': 'B. N. Rau', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 398, 'bleu_score': 0.970362113628587, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2736642774141643804}, 'section': 'Section::::Abstract.'}]}]