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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 cancelTickByTickData(self, contract: Contract, tickType: str):
 """ Unsubscribe from tick-by-tick data Args: contract: The exact contract object that was used to subscribe with. """

        ticker = self.ticker(contract)
        reqId = self.wrapper.endTicker(ticker, tickType)
        if reqId:
            self.client.cancelTickByTickData(reqId)
        else:
            self._logger.error(
                f'cancelMktData: No reqId found for contract {contract}')