Get and merge the `bfd` config from global BGP.

        You should not use this method.
        You probably want `BGP.bfd`.

        Args:
            tx: XML document with the XML to get the transmit interval.
            rx: XML document with the XML to get the receive interval.
            multiplier: XML document with the XML to get the interval
                multiplier.

        Returns:
            Merged XML document.

        Raises:
            None

def _peer_get_bfd(self, tx, rx, multiplier):
        """Get and merge the `bfd` config from global BGP.

        You should not use this method.
        You probably want `BGP.bfd`.

        Args:
            tx: XML document with the XML to get the transmit interval.
            rx: XML document with the XML to get the receive interval.
            multiplier: XML document with the XML to get the interval
                multiplier.

        Returns:
            Merged XML document.

        Raises:
            None
        """
        tx = self._callback(tx, handler='get_config')
        rx = self._callback(rx, handler='get_config')
        multiplier = self._callback(multiplier, handler='get_config')
        tx = pynos.utilities.return_xml(str(tx))
        rx = pynos.utilities.return_xml(str(rx))
        multiplier = pynos.utilities.return_xml(str(multiplier))
        config = pynos.utilities.merge_xml(tx, rx)
        return pynos.utilities.merge_xml(config, multiplier)