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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, tar_file, directory):
 """ Unpacks tar archive to selected directory """


        self.log.info("Unpacking %s tar file to %s directory" %
                      (tar_file, directory))

        with tarfile.open(tar_file, 'r') as tar:
            tar.extractall(path=directory)

        self.log.info("Archive unpacked!")