user: Question: Who directed the episode that had 3.55 million viewers?
Columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'U.S. viewers (million)']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'text']
Sample row: [31.0, 1.0, '" Go Big or Go Home "', 'Dean Holland', 'Alan Yang', 'January20,2011', '6.14']
SQL:

assistant: SELECT "Directed by" FROM "Table" WHERE "U.S. viewers (million)" = '3.55';