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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 _close_kernel_socket(self):
 """Close kernel socket in outdated Python versions. On old Python versions, Python's socket module does NOT call close on the kernel socket when you call socket.close(). We do so manually here because we want this server to send a FIN TCP segment immediately. Note this must be called *before* calling socket.close(), because the latter drops its reference to the kernel socket. """

        if six.PY2 and hasattr(self.socket, '_sock'):
            self.socket._sock.close()