Question: when did south africa win the african cup of nations
[{'answer': '1996', 'provenance': [{'wikipedia_id': '1018598', 'title': 'South Africa national football team', 'start_paragraph_id': 1, 'start_character': 484, 'end_paragraph_id': 1, 'end_character': 488, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]