Question: who has written the national anthem of sri lanka
[{'answer': 'Ananda Samarakoon', 'provenance': [{'wikipedia_id': '287724', 'title': 'Sri Lanka Matha', 'start_paragraph_id': 3, 'start_character': 126, 'end_paragraph_id': 3, 'end_character': 143, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '287724', 'title': 'Sri Lanka Matha', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 936, 'bleu_score': 0.9872197907830691, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5460419386658976262}, 'section': 'Section::::History.\n'}]}]