Question: when did the us recognize texas as an independent nation
[{'answer': 'March 1837', 'provenance': [{'wikipedia_id': '25457', 'title': 'Republic of Texas', 'start_paragraph_id': 2, 'start_character': 425, 'end_paragraph_id': 2, 'end_character': 435, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '25457', 'title': 'Republic of Texas', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 471, 'bleu_score': 0.8588663327033761, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8576235755253764138}, 'section': 'Section::::Abstract.'}]}]