Question: where is the u21 euro championships being held
[{'answer': 'Poland', 'provenance': [{'wikipedia_id': '40944836', 'title': '2017 UEFA European Under-21 Championship', 'start_paragraph_id': 1, 'start_character': 305, 'end_paragraph_id': 1, 'end_character': 311, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '40944836', 'title': '2017 UEFA European Under-21 Championship', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 554, 'bleu_score': 0.7927519398437171, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4379903880729617170}, 'section': 'Section::::Abstract.'}]}]