python run a system command

import subprocess

def runcmd(cmd, verbose = False, *args, **kwargs):

    process = subprocess.Popen(
        cmd,
        stdout = subprocess.PIPE,
        stderr = subprocess.PIPE,
        text = True,
        shell = True
    )
    std_out, std_err = process.communicate()
    if verbose:
        print(std_out.strip(), std_err)
    pass

runcmd('echo "Hello, World!"', verbose = True)

import os
cmd = "git --version"
returned_value = os.system(cmd)  # returns the exit code in unix

Use the subprocess module in the standard library:

import subprocess subprocess.run(["ls", "-l"]) 
The advantage of subprocess.run over os.system is that it is more flexible (you can get the stdout, stderr, the "real" status code, better error handling, etc...).

Even the documentation for os.system recommends using subprocess instead:

The subprocess module provides more powerful facilities for spawning new processes and retrieving their results; using that module is preferable to using this function. See the Replacing Older Functions with the subprocess Module section in the subprocess documentation for some helpful recipes.

On Python 3.4 and earlier, use subprocess.call instead of .run:

subprocess.call(["ls", "-l"])