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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 extract_shn (archive, compression, cmd, verbosity, interactive, outdir):
 """Decompress a SHN archive to a WAV file."""

    cmdlist = [util.shell_quote(cmd)]
    outfile = util.get_single_outfile(outdir, archive, extension=".wav")
    cmdlist.extend(['-x', '-', util.shell_quote(outfile), '<',
        util.shell_quote(archive)])
    return (cmdlist, {'shell': True})