Question: who is the waitress on it's always sunny in philadelphia
[{'answer': 'Mary Elizabeth Ellis', 'provenance': [{'wikipedia_id': '49243651', 'title': "The Waitress (It's Always Sunny in Philadelphia)", 'start_paragraph_id': 1, 'start_character': 140, 'end_paragraph_id': 1, 'end_character': 160, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '49243651', 'title': "The Waitress (It's Always Sunny in Philadelphia)", 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 160, 'bleu_score': 0.729375816975773, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12595839780184911151}, 'section': 'Section::::Abstract.'}]}]