Question: when was wrath of the lich king announced
[{'answer': 'August 3 , 2007', 'provenance': [{'wikipedia_id': '12563163', 'title': 'World of Warcraft: Wrath of the Lich King', 'start_paragraph_id': 26, 'start_character': 61, 'end_paragraph_id': 26, 'end_character': 76, 'bleu_score': 1.0, 'section': 'Section::::Development and release.\n'}]}, {'provenance': [{'wikipedia_id': '12563163', 'title': 'World of Warcraft: Wrath of the Lich King', 'start_paragraph_id': 26, 'start_character': 0, 'end_paragraph_id': 26, 'end_character': 412, 'bleu_score': 0.9226596185977011, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10811413550560157253}, 'section': 'Section::::Development and release.\n'}]}]