Question: who plays young tom riddle in half blood prince
[{'answer': 'Hero Beauregard Fiennes - Tiffin'}, {'provenance': [{'wikipedia_id': '18657642', 'title': 'Hero Fiennes-Tiffin', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 357, 'bleu_score': 0.601654633890604, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9116865142707586278}, 'section': 'Section::::Abstract.'}]}]