Question: where does the superior vena cava return blood from
[{'answer': 'upper limbs', 'provenance': [{'wikipedia_id': '242140', 'title': 'Superior vena cava', 'start_paragraph_id': 3, 'start_character': 121, 'end_paragraph_id': 3, 'end_character': 132, 'bleu_score': 1.0, 'section': 'Section::::Structure.\n'}]}, {'answer': 'eyes', 'provenance': [{'wikipedia_id': '242140', 'title': 'Superior vena cava', 'start_paragraph_id': 3, 'start_character': 134, 'end_paragraph_id': 3, 'end_character': 138, 'bleu_score': 1.0, 'section': 'Section::::Structure.\n'}]}, {'answer': 'neck', 'provenance': [{'wikipedia_id': '242140', 'title': 'Superior vena cava', 'start_paragraph_id': 3, 'start_character': 143, 'end_paragraph_id': 3, 'end_character': 147, 'bleu_score': 1.0, 'section': 'Section::::Structure.\n'}]}, {'provenance': [{'wikipedia_id': '242140', 'title': 'Superior vena cava', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 620, 'bleu_score': 0.8807734172640971, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11371029036811079287}, 'section': 'Section::::Structure.\n'}]}]