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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 pack(self):
 """ Encode a BFD Control packet without authentication section. """

        diag = (self.ver << 5) + self.diag
        flags = (self.state << 6) + self.flags
        length = len(self)

        return struct.pack(self._PACK_STR, diag, flags, self.detect_mult,
                           length, self.my_discr, self.your_discr,
                           self.desired_min_tx_interval,
                           self.required_min_rx_interval,
                           self.required_min_echo_rx_interval)