Question: who was the first sri lankan politician who held the office of the prime minister for four times
[{'answer': 'Ranil Wickramasinghe', 'provenance': [{'wikipedia_id': '31411178', 'title': 'List of Prime Ministers of Sri Lanka', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 20, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '31411178', 'title': 'List of Prime Ministers of Sri Lanka', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 283, 'bleu_score': 0.8059909322159651, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13005771774153894253}, 'section': 'Section::::Abstract.'}]}]