user: Question: How many contestants were there in a season where alejandra espinoza won?
Columns: ['Season', 'Season Premiere', 'Season Finale', 'Winner', 'Runner-up', 'Number of Contestants', "Winner's Country", "Runner Up's Country"]
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['Nuestra Belleza Latina 2007', 'March 27, 2007', 'May 25, 2007', 'Alejandra Espinoza', 'Mayra Muñoz', 12.0, 'Mexico', 'El Salvador']
SQL:

assistant: SELECT "Number of Contestants" FROM "Table" WHERE "Winner" = 'alejandra espinoza';