Question: who has the highest average in test cricket
[{'answer': 'Sir Donald Bradman', 'provenance': [{'wikipedia_id': '18933273', 'title': 'Batting average', 'start_paragraph_id': 4, 'start_character': 188, 'end_paragraph_id': 4, 'end_character': 206, 'bleu_score': 1.0, 'section': 'Section::::Cricket.\n'}]}]