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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 GetSecurityDescriptor(self):
 """Retrieves the security descriptor. Returns: pyfwnt.security_descriptor: security descriptor. """

    fwnt_security_descriptor = pyfwnt.security_descriptor()
    fwnt_security_descriptor.copy_from_byte_stream(
        self._fsntfs_file_entry.security_descriptor_data)

    return fwnt_security_descriptor