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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 create_shn (archive, compression, cmd, verbosity, interactive, filenames):
 """Compress a WAV file to a SHN archive."""

    if len(filenames) > 1:
        raise util.PatoolError("multiple filenames for shorten not supported")
    cmdlist = [util.shell_quote(cmd)]
    cmdlist.extend(['-', util.shell_quote(archive), '<',
        util.shell_quote(filenames[0])])
    return (cmdlist, {'shell': True})