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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_descriptor(self, number):
 """Close file descriptor and remove underlying files."""

        self.descriptors[number]['stdout'].close()
        self.descriptors[number]['stderr'].close()

        if os.path.exists(self.descriptors[number]['stdout_path']):
            os.remove(self.descriptors[number]['stdout_path'])

        if os.path.exists(self.descriptors[number]['stderr_path']):
            os.remove(self.descriptors[number]['stderr_path'])