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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_cache(self):
 """Clear all kinds of internal caches to release resources. Currently persistent commands will be interrupted. :return: self"""

        for cmd in (self.cat_file_all, self.cat_file_header):
            if cmd:
                cmd.__del__()

        self.cat_file_all = None
        self.cat_file_header = None
        return self