What is the total number of grids for peter gethin?
CREATE TABLE table_78426 (
    "Driver" text,
    "Constructor" text,
    "Laps" real,
    "Time/Retired" text,
    "Grid" real
)
SELECT SUM("Grid") FROM table_78426 WHERE "Driver" = 'peter gethin'
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: What is the total number of grids for peter gethin? ### Input: CREATE TABLE table_78426 (
    "Driver" text,
    "Constructor" text,
    "Laps" real,
    "Time/Retired" text,
    "Grid" real
) ### Response: SELECT SUM("Grid") FROM table_78426 WHERE "Driver" = 'peter gethin'