It's much better practise to avoid using sys.exit() and instead raise/handle exceptions to allow the program to finish cleanly. If you want to turn off traceback, simply use:
sys.trackbacklimit=0
You can set this at the top of your script to squash all traceback output, but I prefer to use it more sparingly, for example "known errors" where I want the output to be clean, e.g. in the file foo.py:
import sys
from subprocess import *
try:
check_call([ 'uptime', '--help' ])
except CalledProcessError:
sys.tracebacklimit=0
print "Process failed"
raise
print "This message should never follow an error."
If CalledProcessError is caught, the output will look like this:
[me@test01 dev]$ ./foo.py
usage: uptime [-V]
-V display version
Process failed
subprocess.CalledProcessError: Command '['uptime', '--help']' returned non-zero exit status 1
If any other error occurs, we still get the full traceback output.