Question: when did the kraft heinz merger take place
[{'answer': '2015', 'provenance': [{'wikipedia_id': '46223282', 'title': 'Kraft Heinz', 'start_paragraph_id': 4, 'start_character': 151, 'end_paragraph_id': 4, 'end_character': 155, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}]