Question: who developed an explanation for the photoelectric effect
[{'answer': 'Albert Einstein', 'provenance': [{'wikipedia_id': '23579', 'title': 'Photoelectric effect', 'start_paragraph_id': 3, 'start_character': 193, 'end_paragraph_id': 3, 'end_character': 208, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '23579', 'title': 'Photoelectric effect', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 765, 'bleu_score': 0.8090618274622211, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9210687542192552479}, 'section': 'Section::::Abstract.'}]}]