Question: when was the treaty of brest litovsk signed
[{'answer': '3 March 1918', 'provenance': [{'wikipedia_id': '31388', 'title': 'Treaty of Brest-Litovsk', 'start_paragraph_id': 19, 'start_character': 236, 'end_paragraph_id': 19, 'end_character': 248, 'bleu_score': 1.0, 'section': 'Section::::Peace negotiations.\n'}]}, {'provenance': [{'wikipedia_id': '31388', 'title': 'Treaty of Brest-Litovsk', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 611, 'bleu_score': 0.6546045612465681, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10747728268586070640}, 'section': 'Section::::Abstract.'}]}]