Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
Clarence and Rell (Key and Peale) are two nerds who get mixed up with drug dealers because of a stray kitten named Keanu that was stolen from Rell. They go to a strip club to find Keanu. When upstairs meeting the head of a drug gang named Chedder, Rell is frightened by a large python crawling on the floor but Chedder tells him: "Don't worry about her, man, that's Montana." Rell is so frightened he asks to go to the bathroom to drain his own snake.
Later, Chedder tells his gangsters to throw a drug dealer (WIll Forte) in the back of their SUV and when the hood is opened we see a large python. (An African Rock Python, I believe.) The guy starts screaming in terror at being locked in the trunk with it. When the police open the trunk he is tied up with the snake surrounding him, screaming hysterically for someone to kill the snake because it hurts so bad. (This was so absurd I didn't even bother trying to figure out what the snake could do that could possibly hurt so bad.) Instead of a real python, this time we see a large fake python. Maybe Will Forte is really scared of snakes and refused to work with one, maybe they couldn't rent another that looked the same, or it's possible that they used a fake in order to keep from overworking and overstressing the real snake. Maybe there's a snake union now. Maybe they have SAG cards and all that. Maybe not.