Question: when did the song white christmas come out
[{'answer': '1942', 'provenance': [{'wikipedia_id': '2817215', 'title': 'White Christmas (song)', 'start_paragraph_id': 1, 'start_character': 23, 'end_paragraph_id': 1, 'end_character': 27, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2817215', 'title': 'White Christmas (song)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 299, 'bleu_score': 0.724301013618444, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16092363168151846385}, 'section': 'Section::::Abstract.'}]}]