So far there have been just three actual films “by” Judd Apatow, and this is his best. Funny People revolves around George Simmons (Adam Sandler), a famous comic actor who learns that he has incurable leukemia, and who sets out to rediscover — well, something. George hires a hapless young comic Ira (Seth Rogen) to be his personal assistant and joke-writer. Together they begin a bittersweet …