Question: who are the hosts of australian ninja warrior
[{'answer': 'Rebecca Maddern', 'provenance': [{'wikipedia_id': '51157068', 'title': 'Australian Ninja Warrior', 'start_paragraph_id': 3, 'start_character': 223, 'end_paragraph_id': 3, 'end_character': 238, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'answer': 'Ben Fordham', 'provenance': [{'wikipedia_id': '51157068', 'title': 'Australian Ninja Warrior', 'start_paragraph_id': 3, 'start_character': 293, 'end_paragraph_id': 3, 'end_character': 304, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '51157068', 'title': 'Australian Ninja Warrior', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 425, 'bleu_score': 0.970795021215021, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4975349841864539618}, 'section': 'Section::::History.\n'}]}]