Question: when is the draw for europa league knockout stages
[{'answer': '11 December 2017', 'provenance': [{'wikipedia_id': '54326299', 'title': '2017–18 UEFA Europa League knockout phase', 'start_paragraph_id': 17, 'start_character': 41, 'end_paragraph_id': 17, 'end_character': 57, 'bleu_score': 1.0, 'section': 'Section::::Round of 32.\n'}]}, {'answer': '23 February 2018', 'provenance': [{'wikipedia_id': '54326299', 'title': '2017–18 UEFA Europa League knockout phase', 'start_paragraph_id': 40, 'start_character': 41, 'end_paragraph_id': 40, 'end_character': 57, 'bleu_score': 1.0, 'section': 'Section::::Round of 16.\n'}]}, {'answer': '16 March 2018', 'provenance': [{'wikipedia_id': '54326299', 'title': '2017–18 UEFA Europa League knockout phase', 'start_paragraph_id': 55, 'start_character': 44, 'end_paragraph_id': 55, 'end_character': 57, 'bleu_score': 1.0, 'section': 'Section::::Quarter-finals.\n'}]}, {'answer': '13 April 2018', 'provenance': [{'wikipedia_id': '54326299', 'title': '2017–18 UEFA Europa League knockout phase', 'start_paragraph_id': 67, 'start_character': 41, 'end_paragraph_id': 67, 'end_character': 54, 'bleu_score': 1.0, 'section': 'Section::::Semi-finals.\n'}]}]