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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 clear(self):
 """Clears all data from the data store permanently"""

        for root, dirs, files in os.walk(self._root_dir, topdown=False):
            for file in files:
                os.unlink(os.path.join(root, file))
            os.rmdir(root)
        # Get the root dir back and re-initialise to start again
        root_dir = os.path.abspath(
            os.path.join(self._root_dir, os.pardir))
        self.__init__(root_dir)