import shutil, subprocess

cmd = shutil.which("python3")
runner = subprocess.run([cmd, "--version"], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL) # --> Python 3.7.3
runner.resultcode # --> 0

runner = subprocess.run([cmd, "--version"], shell=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL) # --> stderr bc shell=True is similar to calling `sh python3 --version` which will error
runner.resultcode # --> 127