How to use subprocess methods in general.

execute.py

from subprocess import STDOUT, CalledProcessError, check_output


class SomethingYouWant:
    def __init__(self, working_dir):
        self.working_dir= working_dir
   
    def _build_cmd(self, cmd):
        return cmd.split(' ')
    
    def execute(self, cmd, cwd=None, kill_after_timeout=None, with_extended_output=False, shell=False, env=None):
        """ Handle executing the command on the shell and return the returned information.
         :param cmd:
            The cmd argument list to execute.
            It should be a string, or a sequence of program arguments. The
            program to execute is the first item in the args sequence or string.

        :param env:
            A dictionary of environment variables to be passed to `subprocess.Popen`.

        :param shell:
             Whether to invoke commands through a shell (see `Popen(..., shell=True)`).
             It overrides :attr:`USE_SHELL` if it is not `None`.

        :param kill_after_timeout:
            To specify a timeout in seconds for the git command, after which the process
            should be killed.
        """
        print("Debug cmd: {}".format(cmd))

        if cwd is None:
            cwd = self.working_dir

        inline_env = env
        env = os.environ.copy()
        env["LANGUAGE"] = "C"
        env["LC_ALL"] = "C"

        if inline_env is not None:
            env.update(inline_env)

        if shell is False:
            cmd = self._build_cmd(cmd)

        status = 0
        stdout_value = stderr_value = ''

        try:
            stdout_value = check_output(
                cmd,
                cwd=cwd,
                env=env,
                stderr=STDOUT, # If You want to capture stderr as well.
                shell=shell,
                encoding='utf-8', # Care should be taken with encoding!
            )
        except CalledProcessError as e:
            stderr_value = e.output
            status = e.returncode

        print("Debug return:", status, stdout_value, stderr_value)

        if with_extended_output:
            return (status, stdout_value.strip(), stderr_value.strip())
        else:
            return status