code: def read(cls, proto):
      
      # Use base class to create initial class from proto.baseTM
      # (BacktrackingTMProto)
      obj = BacktrackingTM.read(proto.baseTM)
      obj.__class__ = cls
  
      # Additional CPP-specific deserialization
      newCells4 = Cells4.read(proto.cells4)
      print newCells4
      obj.cells4 = newCells4
      obj.makeCells4Ephemeral = proto.makeCells4Ephemeral
      obj.seed = proto.seed
      obj.checkSynapseConsistency = proto.checkSynapseConsistency
      obj._initArgsDict = json.loads(proto.initArgs)
      # Convert unicode to str
      obj._initArgsDict["outputType"] = str(obj._initArgsDict["outputType"])
  
      # Initialize ephemeral attributes
      obj.allocateStatesInCPP = False
      obj.retrieveLearningStates = False
      obj._setStatePointers()
  
      return obj
docs: Deserialize from proto instance.
  
      :param proto: (BacktrackingTMCppProto) the proto instance to read from