what exactly is a query structure?

hello.

Postgresql 8.3.9

CREATE TYPE usr_secrets AS (login TEXT, pass TEXT, shop_pass TEXT);

CREATE OR REPLACE FUNCTION get_noobs () RETURNS SETOF usr_secrets AS $$
BEGIN  RETURN QUERY SELECT login, '*' as pass, shop_pass FROM noob;  RETURN;
END;
$$ LANGUAGE plpgsql SECURITY DEFINER;

SELECT * from get_noobs();

And we have the following error

ERROR:  structure of query does not match function result type