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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 FromTrimmedData(byts):
 """ Deserialize a block from raw bytes. Args: byts: Returns: Block: """

        block = Block()
        block.__is_trimmed = True
        ms = StreamManager.GetStream(byts)
        reader = BinaryReader(ms)

        block.DeserializeUnsigned(reader)
        reader.ReadByte()
        witness = Witness()
        witness.Deserialize(reader)
        block.Script = witness

        bc = GetBlockchain()
        tx_list = []
        for tx_hash in reader.ReadHashes():
            tx = bc.GetTransaction(tx_hash)[0]
            if not tx:
                raise Exception("Could not find transaction!\n Are you running code against a valid Blockchain instance?\n Tests that accesses transactions or size of a block but inherit from NeoTestCase instead of BlockchainFixtureTestCase will not work.")
            tx_list.append(tx)

        if len(tx_list) < 1:
            raise Exception("Invalid block, no transactions found for block %s " % block.Index)

        block.Transactions = tx_list

        StreamManager.ReleaseStream(ms)

        return block