NameError: name 'exit' is not defined

I used cxfreeze to create a Windows executable from planrequest.py. It seemed to work ok, but when I run the exe file I get NameError: name 'exit' is not defined

name exit is not defined in python states that the fix is to use import sys. However, I use import sys. The code runs fine as a python script (as in, I extensively tested the command line arguments before compiling to an executable.)

import socket
import sys

if len(sys.argv) == 1:
    print("Usage:")
    print("PlanRequest [Request String] [Server IP (optional: assumes 127.0.0.1 if omitted)]")
    exit()

#[do stuff with the request]