 what number of titles have talib kweli greene as a sole songwriter ?
CREATE TABLE table_203_687 (
    id number,
    "#" number,
    "title" text,
    "time" text,
    "performer(s)" text,
    "songwriters" text,
    "producer(s)" text,
    "samples and notes" text
)
SELECT COUNT("title") FROM table_203_687 WHERE "songwriters" = 'talib kweli greene' AND "songwriters" = 1