Question: the back of the leg is called what
[{'answer': 'calf', 'provenance': [{'wikipedia_id': '39595', 'title': 'Human leg', 'start_paragraph_id': 5, 'start_character': 74, 'end_paragraph_id': 5, 'end_character': 78, 'bleu_score': 1.0, 'section': 'Section::::Structure.\n'}]}, {'provenance': [{'wikipedia_id': '39595', 'title': 'Human leg', 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 193, 'bleu_score': 0.8846179250781581, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14892194212484222383}, 'section': 'Section::::Structure.\n'}]}]