user: Question: What episode title had a production code of 3X6306?
Columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (million)']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [55.0, 1.0, '" Chuck Versus the Anniversary "', 'Robert Duncan McNeill', 'Chris Fedak', 'September20,2010', '3X6301', '5.79']
SQL:

assistant: SELECT "Title" FROM "Table" WHERE "Production code" = '3X6306';