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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 _decompress(self, cmd, s3_snap):
 """Adds the appropriate command to decompress the zfs stream This is determined from the metadata of the s3_snap. """

        compressor = COMPRESSORS.get(s3_snap.compressor)
        if compressor is None:
            return cmd
        decompress_cmd = compressor['decompress']
        return "{} | {}".format(decompress_cmd, cmd)