old_contents: 
  from neo.IO.Mixins import SerializableMixin
  import mmh3
  
  
  class StorageKey(SerializableMixin):
  
      ScriptHash = None
      Key = None
  
  
      def __init__(self, script_hash=None, key=None):
          self.ScriptHash = script_hash
          self.Key = key
  
      def _murmur(self):
          return mmh3.hash(self.Key)
  
      def GetHashCode(self):
          return abs(self.ScriptHash.GetHashCode() + self._murmur())
  
      def GetHashCodeBytes(self):
          return self.GetHashCode().to_bytes(8, 'little')
  
      def Deserialize(self, reader):
          self.ScriptHash = reader.ReadUInt160()
          self.Key = reader.ReadBytes()
  
      def Serialize(self, writer):
          writer.WriteUInt160(self.ScriptHash)
          writer.WriteVarBytes(self.Key)
  
      def __eq__(self, other):
          if other is None:
              return False
          if other is self:
              return True
  
          return self.ScriptHash == other.ScriptHash and self.Key == other.Key
  
new_contents: 
  from neo.IO.Mixins import SerializableMixin
  import mmh3
  
  
  class StorageKey(SerializableMixin):
  
      ScriptHash = None
      Key = None
  
  
      def __init__(self, script_hash=None, key=None):
          self.ScriptHash = script_hash
          self.Key = key
  
      def _murmur(self):
          return mmh3.hash(bytes(self.Key))
  
      def GetHashCode(self):
          return abs(self.ScriptHash.GetHashCode() + self._murmur())
  
      def GetHashCodeBytes(self):
          return self.GetHashCode().to_bytes(8, 'little')
  
      def Deserialize(self, reader):
          self.ScriptHash = reader.ReadUInt160()
          self.Key = reader.ReadBytes()
  
      def Serialize(self, writer):
          writer.WriteUInt160(self.ScriptHash)
          writer.WriteVarBytes(self.Key)
  
      def __eq__(self, other):
          if other is None:
              return False
          if other is self:
              return True
  
          return self.ScriptHash == other.ScriptHash and self.Key == other.Key
  
subject: fix for readonly bytearray issue with murmur library