Question: who was the last team to win back-to-back world cups
[{'answer': 'Brazil', 'provenance': [{'wikipedia_id': '27818578', 'title': 'List of FIFA World Cup winners', 'start_paragraph_id': 3, 'start_character': 71, 'end_paragraph_id': 3, 'end_character': 77, 'bleu_score': 1.0, 'section': 'Section::::By team.\n'}]}]