Question: when did gen 2 come out pokemon go
[{'answer': 'February 2017', 'provenance': [{'wikipedia_id': '47774416', 'title': 'Pokémon Go', 'start_paragraph_id': 15, 'start_character': 1152, 'end_paragraph_id': 15, 'end_character': 1165, 'bleu_score': 1.0, 'section': 'Section::::Development.\n'}]}, {'provenance': [{'wikipedia_id': '47774416', 'title': 'Pokémon Go', 'start_paragraph_id': 15, 'start_character': 0, 'end_paragraph_id': 15, 'end_character': 1733, 'bleu_score': 0.989901732545244, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12562790609808840688}, 'section': 'Section::::Development.\n'}]}]