shell_with_env.py

import subprocess
import os


def get_user_shell():
    USR_BIN_BASH = "/usr/bin/bash"
    BIN_BASH = "/bin/bash"
    default_shell = USR_BIN_BASH if os.path.exists(USR_BIN_BASH) else BIN_BASH if os.path.exists(BIN_BASH) else None
    shell = os.environ.get("DEFAULT_SHELL",  os.environ.get("SHELL", default_shell))
    if shell is None:
        raise RuntimeError("Cannot find suitable shell")
    return shell


def shell_with_env(shell_env):
    env = os.environ.copy()
    env.update(shell_env)
    return subprocess.Popen(
        args=[get_user_shell()],
        shell=True,
        env=env,
        start_new_session=True
    ).wait()


def main():
    new_env = {
        "hello": "world"
    }
    result = shell_with_env(new_env)
    print("Exited with: %s" % result)


if __name__ == '__main__':
    main()