Question: where was the opening ceremony of ipl (2013) held on 2 april 2013
[{'answer': 'Salt Lake Stadium in Kolkata', 'provenance': [{'wikipedia_id': '34619694', 'title': '2013 Indian Premier League', 'start_paragraph_id': 1, 'start_character': 306, 'end_paragraph_id': 1, 'end_character': 334, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '34619694', 'title': '2013 Indian Premier League', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 732, 'bleu_score': 0.984789766484456, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6893953147730012956}, 'section': 'Section::::Abstract.'}]}]