Python Ctypes - CreateProcessW doesn't spawn a process

Question

Ctypes's windll.kernel32.CreateProcessW function doesn't execute/spawn any process when used as follows:

import ctypes
ctypes.windll.kernel32.CreateProcessW("cmstp","", None, None, False, 0, None, None, None, None) # Should start a process

Any idea why? I have tried using 0 instead of None, putting cmstp in 2nd arg, both, etc.