Question: president of congress session in 1929 at lahore
[{'answer': 'Jawaharlal Nehru', 'provenance': [{'wikipedia_id': '2012055', 'title': 'List of Presidents of the Indian National Congress', 'start_paragraph_id': 2, 'start_character': 196, 'end_paragraph_id': 2, 'end_character': 212, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}]