Question: what is the oldest mlb stadium still in use
[{'answer': 'Fenway Park in Boston', 'provenance': [{'wikipedia_id': '643381', 'title': 'List of current Major League Baseball stadiums', 'start_paragraph_id': 2, 'start_character': 151, 'end_paragraph_id': 2, 'end_character': 172, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '643381', 'title': 'List of current Major League Baseball stadiums', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 238, 'bleu_score': 0.9517713210466091, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11364595198026861942}, 'section': 'Section::::Abstract.'}]}]