user: Question: What is the nationality of the player with a transfer fee of £400k?
Columns: ['Nat.', 'Name', 'Since', 'Goals', 'Transfer fee']
Types: ['text', 'text', 'text', 'real', 'text']
Sample row: ['FRA', 'Larrieu', '2000', 0.0, 'Free']
SQL:

assistant: SELECT "Nat." FROM "Table" WHERE "Transfer fee" = '£400k';