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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def run_module_command(cmd_list, env_vars, exit_on_error=True):
 """Shell out to provisioner command."""

    if exit_on_error:
        try:
            subprocess.check_call(cmd_list, env=env_vars)
        except subprocess.CalledProcessError as shelloutexc:
            sys.exit(shelloutexc.returncode)
    else:
        subprocess.check_call(cmd_list, env=env_vars)