Question: who is the first president of all india trade union congress
[{'answer': 'Lala Lajpat Rai', 'provenance': [{'wikipedia_id': '1680413', 'title': 'All India Trade Union Congress', 'start_paragraph_id': 2, 'start_character': 39, 'end_paragraph_id': 2, 'end_character': 54, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]