Question: american actress who plays lead in madam secretary
[{'answer': 'Téa Leoni', 'provenance': [{'wikipedia_id': '42740374', 'title': 'Madam Secretary (TV series)', 'start_paragraph_id': 1, 'start_character': 99, 'end_paragraph_id': 1, 'end_character': 108, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]