Question: where is the mediastinum located in the human body
[{'answer': 'within the thorax', 'provenance': [{'wikipedia_id': '1341634', 'title': 'Mediastinum', 'start_paragraph_id': 1, 'start_character': 213, 'end_paragraph_id': 1, 'end_character': 230, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1341634', 'title': 'Mediastinum', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 374, 'bleu_score': 0.9716239638199891, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4111194432097062069}, 'section': 'Section::::Structure.\n'}]}]