MySQL 8.4

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select version();

version()

8.4.3

CREATE TABLE auth_user (first_name text, username text);
INSERT INTO auth_user (first_name, username) VALUES ('Bob', 'bob'), ('Bob', 'bob2');

Records: 2  Duplicates: 0  Warnings: 0

SELECT distinct (first_name), username FROM auth_user WHERE 1; 

first_name
username

Bob
bob

Bob
bob2