user: Question: What is the builder of the train with LMS Class 3F?
Columns: ['Class', 'Wheels', 'Date', 'Builder', 'No. built', '1919 nos.', 'LMS Class', 'LMS nos.']
Types: ['text', 'real', 'text', 'text', 'real', 'text', 'text', 'text']
Sample row: ['4-4-0', 131.0, '1913', 'North British', 6.0, '331-336', '3P', '14510-5']
SQL:

assistant: SELECT "Builder" FROM "Table" WHERE "LMS Class" = '3F';