What is the highest Bronze, when Nation is 'South Africa', and when Total is less than 20?
CREATE TABLE table_name_73 (
    bronze INTEGER,
    nation VARCHAR,
    total VARCHAR
)
SELECT MAX(bronze) FROM table_name_73 WHERE nation = "south africa" AND total < 20
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 highest Bronze, when Nation is 'South Africa', and when Total is less than 20? ### Input: CREATE TABLE table_name_73 (
    bronze INTEGER,
    nation VARCHAR,
    total VARCHAR
) ### Response: SELECT MAX(bronze) FROM table_name_73 WHERE nation = "south africa" AND total < 20