Question: who serves as head of their political party
[{'answer': 'a party leader', 'provenance': [{'wikipedia_id': '9476145', 'title': 'Party leader', 'start_paragraph_id': 1, 'start_character': 26, 'end_paragraph_id': 1, 'end_character': 40, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '9476145', 'title': 'Party leader', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 438, 'bleu_score': 0.5476491671907661, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4547576361448465510}, 'section': 'Section::::Abstract.'}]}]