Question: when did the pittsburgh penguins enter the nhl
[{'answer': 'February 8 , 1966', 'provenance': [{'wikipedia_id': '66964', 'title': 'Pittsburgh Penguins', 'start_paragraph_id': 5, 'start_character': 1006, 'end_paragraph_id': 5, 'end_character': 1023, 'bleu_score': 1.0, 'section': 'Section::::Team history.:Early years (1967–1984).\n'}]}, {'provenance': [{'wikipedia_id': '66964', 'title': 'Pittsburgh Penguins', 'start_paragraph_id': 5, 'start_character': 972, 'end_paragraph_id': 5, 'end_character': 1607, 'bleu_score': 0.8995254298368741, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6597602429366333895}, 'section': 'Section::::Team history.:Early years (1967–1984).\n'}]}]