Question: who is the main actor in the show arrow
[{'answer': 'Stephen Amell', 'provenance': [{'wikipedia_id': '39235131', 'title': 'List of Arrow characters', 'start_paragraph_id': 7, 'start_character': 33, 'end_paragraph_id': 7, 'end_character': 46, 'bleu_score': 1.0, 'section': 'Section::::Main characters.:Oliver Queen / Green Arrow.\n'}]}]