Question: when is the andromeda galaxy colliding with the milky way
[{'answer': 'in about 4 billion years'}, {'provenance': [{'wikipedia_id': '7901784', 'title': 'Andromeda–Milky Way collision', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 431, 'bleu_score': 0.876211083651756, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5993004742488280908}, 'section': 'Section::::Abstract.'}]}]