Question: who are the actors that played dumbledore in harry potter
[{'answer': 'Richard Harris', 'provenance': [{'wikipedia_id': '45322', 'title': 'Albus Dumbledore', 'start_paragraph_id': 2, 'start_character': 28, 'end_paragraph_id': 2, 'end_character': 42, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Michael Gambon', 'provenance': [{'wikipedia_id': '45322', 'title': 'Albus Dumbledore', 'start_paragraph_id': 2, 'start_character': 243, 'end_paragraph_id': 2, 'end_character': 257, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Toby Regbo', 'provenance': [{'wikipedia_id': '45322', 'title': 'Albus Dumbledore', 'start_paragraph_id': 37, 'start_character': 0, 'end_paragraph_id': 37, 'end_character': 10, 'bleu_score': 1.0, 'section': 'Section::::Portrayals within films.\n'}]}, {'answer': 'Jude Law', 'provenance': [{'wikipedia_id': '45322', 'title': 'Albus Dumbledore', 'start_paragraph_id': 2, 'start_character': 326, 'end_paragraph_id': 2, 'end_character': 334, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]