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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 check_tx(self, tx) -> ResponseCheckTx: """ Validate the Tx before entry into the mempool If not an order, a non-zero code is returned and the tx will be dropped. """

        value = decode_number(tx)
        if not value == (self.txCount + 1):
            # respond with non-zero code
            return ResponseCheckTx(code=1)
        return ResponseCheckTx(code=CodeTypeOk)