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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 clean(self):
 """ Remove all of the MOF files and the `schema_mof_dir` for the defined schema. This is useful because while the downloaded schema is a single compressed zip file, it creates several thousand MOF files that take up considerable space. The next time the :class:`~pywbem_mock.DMTFCIMSchema` object for this `schema_version` and `schema_root_dir` is created, the MOF file are extracted again. """

        if os.path.isdir(self.schema_mof_dir):
            shutil.rmtree(self.schema_mof_dir)