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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_directory(self, name):
 """Clean a directory if exists and not in dry run"""

        if not os.path.exists(name):
            return
        self.announce(
            "removing directory '{}' and all its contents".format(name)
        )
        if not self.dry_run:
            rmtree(name, True)