Question: what is penny's last name in big bang theory
[{'answer': 'Hofstadter', 'provenance': [{'wikipedia_id': '21971061', 'title': 'Penny (The Big Bang Theory)', 'start_paragraph_id': 1, 'start_character': 216, 'end_paragraph_id': 1, 'end_character': 226, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '21971061', 'title': 'Penny (The Big Bang Theory)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 1039, 'bleu_score': 0.9632447059224951, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1989517286415403959}, 'section': 'Section::::Abstract.'}]}]