user: Question: What is the sum of all mintage created by Pierre Leduc?
Columns: ['Year', 'Park', 'Artist', 'Mintage', 'Issue Price']
Types: ['real', 'text', 'text', 'real', 'text']
Sample row: [2005.0, 'Pacific Rim (B.C.)', 'Susanna Blunt', 20000.0, '$69.95']
SQL:

assistant: SELECT SUM("Mintage") FROM "Table" WHERE "Artist" = 'Pierre Leduc';