Dalla documentazione del modulo os, oltre a os.system, os.popen e le altre cose suggerite da billiejoex, ecco un po' di altre funzioni (simili fra loro, lo so)

execl(file, *args)

Execute the executable file with argument list args, replacing the
current process.

execlp(file, *args)

Execute the executable file (which is searched for along $PATH)
with argument list args, replacing the current process.

execv(...)

Execute an executable path with arguments, replacing current process.

path: path of executable file
args: tuple or list of strings


execvp(file, args)

Execute the executable file (which is searched for along $PATH)
with argument list args, replacing the current process.
args may be a list or tuple of strings.