Question: when was the ukraine taken over by russia
[{'answer': '20 February 2014', 'provenance': [{'wikipedia_id': '42085878', 'title': 'Russian military intervention in Ukraine (2014–present)', 'start_paragraph_id': 25, 'start_character': 252, 'end_paragraph_id': 25, 'end_character': 268, 'bleu_score': 1.0, 'section': 'Section::::Crimea.:2014 annexation.\n'}]}]