user: Question: what is the average b score when the gymnast is Kōhei Uchimura ( JPN )?
Columns: ['Position', 'Gymnast', 'A Score', 'B Score', 'Total']
Types: ['text', 'text', 'real', 'real', 'real']
Sample row: ['1st', 'Diego Hypólito ( BRA )', 6.6, 9.35, 15.95]
SQL:

assistant: SELECT AVG("B Score") FROM "Table" WHERE "Gymnast" = 'Kōhei Uchimura ( JPN )';