old_contents: from ryu.base import app_manager
  from ryu.controller import ofp_event
  from ryu.controller.handler import CONFIG_DISPATCHER, MAIN_DISPATCHER
  from ryu.controller.handler import set_ev_cls
  from ryu.ofproto import ofproto_v1_3
  from ryu.lib.packet import packet
  from ryu.lib.packet import ethernet
  
  
  def warper(func):
  
      def new_handler(dp, msg):
          print("Msg : {}".format(msg))
          func(dp, msg)
  
      return new_handler
  
  
  class ChangeSendMsg(app_manager.RyuApp):
      OFP_VERSIONS = [ofproto_v1_3.OFP_VERSION]
  
      def __init__(self, *args, **kwargs):
          super(ChangeSendMsg, self).__init__(*args, **kwargs)
  
      @set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER)
      def switch_features_handler(self, ev):
          datapath = ev.msg.datapath
          datapath.send_msg = warper(datapath.send_msg)
  
new_contents: from ryu.base import app_manager
  from ryu.controller import ofp_event
  from ryu.controller.handler import CONFIG_DISPATCHER, MAIN_DISPATCHER
  from ryu.controller.handler import set_ev_cls
  from ryu.ofproto import ofproto_v1_0
  from ryu.lib.packet import packet
  from ryu.lib.packet import ethernet
  
  
  def warper(func):
  
      def new_handler(msg):
          print("Msg : {}".format(msg))
          func(msg)
  
      return new_handler
  
  
  class ChangeSendMsg(app_manager.RyuApp):
      OFP_VERSIONS = [ofproto_v1_0.OFP_VERSION]
  
      def __init__(self, *args, **kwargs):
          super(ChangeSendMsg, self).__init__(*args, **kwargs)
  
      @set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER)
      def switch_features_handler(self, ev):
          datapath = ev.msg.datapath
          datapath.send_msg = warper(datapath.send_msg)
  
  
subject: Fix bugs for ModifyRyuBehavior