user: Question: What stage was 1,648 km achieved?
Columns: ['Year', 'Date', 'Stages', 'Distance', 'Winner']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1955', '28 April–1 May', '4', '418 km', 'Antonio Arzala ( PHI )']
SQL:

assistant: SELECT "Stages" FROM "Table" WHERE "Distance" = '1,648 km';