Question: what is leonard's job on big bang theory
[{'answer': 'Caltech experimental physicist', 'provenance': [{'wikipedia_id': '19606180', 'title': 'Leonard Hofstadter', 'start_paragraph_id': 7, 'start_character': 86, 'end_paragraph_id': 7, 'end_character': 116, 'bleu_score': 1.0, 'section': 'Section::::Characterization.:Personality.\n'}]}, {'provenance': [{'wikipedia_id': '19606180', 'title': 'Leonard Hofstadter', 'start_paragraph_id': 7, 'start_character': 0, 'end_paragraph_id': 7, 'end_character': 1022, 'bleu_score': 0.9720609073682611, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15847340933436612898}, 'section': 'Section::::Characterization.:Personality.\n'}]}]