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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 _unpack(self):
 """Unpacks the CSPICE package on the given root directory. Note that Package could either be the zipfile.ZipFile class for Windows platforms or tarfile.TarFile for other platforms. """

        if self._ext == 'zip':
            with ZipFile(self._local, 'r') as archive:
                archive.extractall(self._root)
        else:
            cmd = 'gunzip | tar xC ' + self._root
            proc = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE)
            proc.stdin.write(self._local.read())
        self._local.close()