old_contents: from enum import Enum
  
  class SessionState(Enum):
      NEW = 0
      CONNECTED = 1
      DISCONNECTED = 2
  
  class Session:
      def __init__(self):
          self.state = SessionState.NEW
          self.reader = None
          self.writer = None
          self.remote_address = None
          self.remote_port = None
          self.local_address = None
          self.local_port = None
          self.client_id = None
          self.clean_session = None
          self.will_flag = False
          self.will_message = None
          self.will_qos = None
          self.will_retain = None
          self.will_topic = None
          self.keep_alive = 0
          self.username = None
          self.password = None
          self.scheme = None
          self._packet_id = 0
          self.parent = 0
  
          self.inflight_out = dict()
          self.inflight_in = dict()
  
      @property
      def next_packet_id(self):
          self._packet_id += 1
          return self._packet_id
  
new_contents: # Copyright (c) 2015 Nicolas JOUANIN
  #
  # See the file license.txt for copying permission.
  from enum import Enum
  
  class SessionState(Enum):
      NEW = 0
      CONNECTED = 1
      DISCONNECTED = 2
  
  class Session:
      def __init__(self):
          self.state = SessionState.NEW
          self.reader = None
          self.writer = None
          self.remote_address = None
          self.remote_port = None
          self.local_address = None
          self.local_port = None
          self.client_id = None
          self.clean_session = None
          self.will_flag = False
          self.will_message = None
          self.will_qos = None
          self.will_retain = None
          self.will_topic = None
          self.keep_alive = 0
          self.username = None
          self.password = None
          self.scheme = None
          self._packet_id = 0
          self.parent = 0
  
          self.inflight_out = dict()
          self.inflight_in = dict()
  
      @property
      def next_packet_id(self):
          self._packet_id += 1
          return self._packet_id
  
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