Question: what type of train is thomas the tank engine
[{'answer': 'a fictional steam locomotive'}, {'provenance': [{'wikipedia_id': '19357739', 'title': 'Thomas the Tank Engine', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 339, 'bleu_score': 0.7187023788151871, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12260751914627687296}, 'section': 'Section::::Abstract.'}]}]