Question: when was the international covenant on civil and political rights signed
[{'answer': '19 December 1966'}, {'provenance': [{'wikipedia_id': '98677', 'title': 'International Covenant on Civil and Political Rights', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 744, 'bleu_score': 0.8577795410871261, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3562656787819382575}, 'section': 'Section::::Abstract.'}]}]