Question: when did the first 3d printer come out
[{'answer': '1981', 'provenance': [{'wikipedia_id': '1305947', 'title': '3D printing', 'start_paragraph_id': 10, 'start_character': 0, 'end_paragraph_id': 10, 'end_character': 4, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}]