根据给定的电影剧本，为角色分配演员。
电影剧本：
FADE IN:

EXT. CITY STREET - DAY

John walks down the busy city street, lost in thought.

INT. JOHN'S APARTMENT - DAY

John enters his shabby apartment and falls onto the couch.

JOHN
(to himself)
What am I doing with my life?

EXT. PARK - DAY

John sits on a bench, staring into space.

角色：
John: ___________________
其他角色: ____________________
John: Unknown, casting needed.
Other characters: None indicated in the given script.