user: Question: What was the quantity of the fleet information for DWWR 50 and 51?
Columns: ['Type', 'Fleet numbers', 'Quantity made', 'Date made', 'GSR Class', 'Inchicore Class', 'GSR Nos.', 'Withdrawn']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['2-2-2WT', 'DWWR 27 and 28', '2', '1869', '—', '—', '—', '1887']
SQL:

assistant: SELECT "Quantity made" FROM "Table" WHERE "Fleet numbers" = 'DWWR 50 and 51';