Question: when was 3 point line added in nba
[{'answer': '1961', 'provenance': [{'wikipedia_id': '2214267', 'title': 'Three-point field goal', 'start_paragraph_id': 5, 'start_character': 292, 'end_paragraph_id': 5, 'end_character': 296, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '2214267', 'title': 'Three-point field goal', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 285, 'bleu_score': 0.5179074676021781, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5912124538658108740}, 'section': 'Section::::History.\n'}]}]