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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def GetHashData(hashable):
 """ Get the data used for hashing. Args: hashable (neo.IO.Mixins.SerializableMixin):
 object extending SerializableMixin Returns: bytes: """

        ms = StreamManager.GetStream()
        writer = BinaryWriter(ms)
        hashable.SerializeUnsigned(writer)
        ms.flush()
        retVal = ms.ToArray()
        StreamManager.ReleaseStream(ms)
        return retVal