Question: who does the voice of our cartoon president
[{'answer': 'Jeff Bergman', 'provenance': [{'wikipedia_id': '56086922', 'title': 'Our Cartoon President', 'start_paragraph_id': 6, 'start_character': 12, 'end_paragraph_id': 6, 'end_character': 24, 'bleu_score': 1.0, 'section': 'Section::::Cast and characters.:Main.\n'}]}, {'provenance': [{'wikipedia_id': '56086922', 'title': 'Our Cartoon President', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 40, 'bleu_score': 0.6147881529512641, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 829619290684952317}, 'section': 'Section::::Cast and characters.:Main.\n'}]}]