Question: who has the most billboard number one albums
[{'answer': 'The Beatles', 'provenance': [{'wikipedia_id': '730350', 'title': 'Billboard 200', 'start_paragraph_id': 40, 'start_character': 12, 'end_paragraph_id': 40, 'end_character': 23, 'bleu_score': 1.0, 'section': 'Section::::Artist milestones.:Most cumulative weeks at number one.\n'}]}]