Add virtual ethernet (ve) interface to the overlay-gateway

               Args:
                   name  (str): gateway-name
                   int_id (int): ve id
                   vrrp_id (int): VRPP-E group ID
                   callback (function): A function executed upon completion of the
                        method.

               Returns:
                  Return value of `callback`.

               Raises:
                   None

def hwvtep_add_ve_interface(self, **kwargs):
        """
               Add virtual ethernet (ve) interface to the overlay-gateway

               Args:
                   name  (str): gateway-name
                   int_id (int): ve id
                   vrrp_id (int): VRPP-E group ID
                   callback (function): A function executed upon completion of the
                        method.

               Returns:
                  Return value of `callback`.

               Raises:
                   None
               """
        name = kwargs.pop('name')
        ve_id = kwargs.pop('ve_id')
        vrrp_id = kwargs.pop('vrrp_id')
        ve_args = dict(name=name, ve_id=ve_id)
        method_name = 'overlay_gateway_ip_interface_ve_ve_id'
        method_class = self._brocade_tunnels
        ve_attr = getattr(method_class, method_name)
        config = ve_attr(**ve_args)
        output = self._callback(config)
        method_name = 'overlay_gateway_ip_interface_ve_vrrp_extended_group'
        vrrp_attr = getattr(method_class, method_name)
        vrrp_args = dict(name=name, vrrp_extended_group=vrrp_id)
        config = vrrp_attr(**vrrp_args)
        output = self._callback(config)

        return output