Question: when did the united states sent troops to vietnam
[{'answer': 'November 1963', 'provenance': [{'wikipedia_id': '32611', 'title': 'Vietnam War', 'start_paragraph_id': 46, 'start_character': 369, 'end_paragraph_id': 46, 'end_character': 382, 'bleu_score': 1.0, 'section': "Section::::Kennedy's escalation, 1961–63.\n"}]}, {'provenance': [{'wikipedia_id': '32611', 'title': 'Vietnam War', 'start_paragraph_id': 46, 'start_character': 0, 'end_paragraph_id': 46, 'end_character': 481, 'bleu_score': 0.97451705556073, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16609152087512910817}, 'section': "Section::::Kennedy's escalation, 1961–63.\n"}]}]