Question: when did germany and the soviet union split poland
[{'answer': '6 October 1939', 'provenance': [{'wikipedia_id': '7884711', 'title': 'Soviet invasion of Poland', 'start_paragraph_id': 1, 'start_character': 315, 'end_paragraph_id': 1, 'end_character': 329, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '7884711', 'title': 'Soviet invasion of Poland', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 591, 'bleu_score': 0.7473851516016851, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4949117587102038485}, 'section': 'Section::::Abstract.'}]}]