Question: when was the first episode of the walking dead aired
[{'answer': 'October 31 , 2010', 'provenance': [{'wikipedia_id': '28074027', 'title': 'List of The Walking Dead episodes', 'start_paragraph_id': 1, 'start_character': 249, 'end_paragraph_id': 1, 'end_character': 266, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]