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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 shell_out(cmd, stderr=STDOUT, cwd=None):
 """Friendlier version of check_output."""

    if cwd is None:
        from os import getcwd
        cwd = getcwd()  # TODO do I need to normalize this on Windows

    out = check_output(cmd, cwd=cwd, stderr=stderr, universal_newlines=True)
    return _clean_output(out)