To what district does Bill Hefner belong?
CREATE TABLE table_18197 (
    "District" text,
    "Incumbent" text,
    "Party" text,
    "First elected" real,
    "Status" text,
    "Opponent" text
)
SELECT "District" FROM table_18197 WHERE "Incumbent" = 'Bill Hefner'
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: To what district does Bill Hefner belong? ### Input: CREATE TABLE table_18197 (
    "District" text,
    "Incumbent" text,
    "Party" text,
    "First elected" real,
    "Status" text,
    "Opponent" text
) ### Response: SELECT "District" FROM table_18197 WHERE "Incumbent" = 'Bill Hefner'