Fix Python – Negation in Python

I’m trying to create a directory if the path doesn’t exist, but the ! (not) operator doesn’t work. I’m not sure how to negate in Python… What’s the correct way to do this?
if (!os.path.exists(“/usr/share/sounds/blues”)):
proc = subprocess.Popen([“mkdir”, “/usr/share/sounds/blues”])
proc.wait()

….