Question: how many times has cristiano ronaldo won world best player
[{'answer': 'four'}, {'provenance': [{'wikipedia_id': '398110', 'title': "Ballon d'Or", 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 758, 'bleu_score': 0.7350891896032851, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6481503114233451497}, 'section': 'Section::::History.\n'}]}]