Question: what is the arjun's bow called in mahabharat
[{'answer': 'Gandiva', 'provenance': [{'wikipedia_id': '1377363', 'title': 'Gandiva', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 7, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]