Question: who are the leaders of kensington and chelsea council
[{'answer': 'Elizabeth Campbell ,', 'provenance': [{'wikipedia_id': '29302013', 'title': 'Kensington and Chelsea London Borough Council', 'start_paragraph_id': 12, 'start_character': 470, 'end_paragraph_id': 12, 'end_character': 488, 'bleu_score': 1.0, 'section': 'Section::::Grenfell Tower fire.\n'}]}]