Question: who has held all 3 grand tours at the same time
[{'answer': 'Eddy Merckx', 'provenance': [{'wikipedia_id': '246893', 'title': 'Triple Crown of Cycling', 'start_paragraph_id': 3, 'start_character': 126, 'end_paragraph_id': 3, 'end_character': 137, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Stephen Roche', 'provenance': [{'wikipedia_id': '246893', 'title': 'Triple Crown of Cycling', 'start_paragraph_id': 3, 'start_character': 142, 'end_paragraph_id': 3, 'end_character': 155, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]