Question: who did elton john write philadelphia freedom for
[{'answer': 'Billie Jean King', 'provenance': [{'wikipedia_id': '5835157', 'title': 'Philadelphia Freedom (song)', 'start_paragraph_id': 2, 'start_character': 95, 'end_paragraph_id': 2, 'end_character': 111, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '5835157', 'title': 'Philadelphia Freedom (song)', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 276, 'bleu_score': 0.9569637990759251, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 278412823052909942}, 'section': 'Section::::Abstract.'}]}]