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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 reqTickByTickData( self, contract: Contract, tickType: str, numberOfTicks: int = 0, ignoreSize: bool = False) -> Ticker: """ Subscribe to tick-by-tick data and return the Ticker that holds the ticks in ticker.tickByTicks. https://interactivebrokers.github.io/tws-api/tick_data.html Args: contract: Contract of interest. tickType: One of 'Last', 'AllLast', 'BidAsk' or 'MidPoint'. numberOfTicks: Number of ticks or 0 for unlimited. ignoreSize: Ignore bid/ask ticks that only update the size. """

        reqId = self.client.getReqId()
        ticker = self.wrapper.startTicker(reqId, contract, tickType)
        self.client.reqTickByTickData(
            reqId, contract, tickType, numberOfTicks, ignoreSize)
        return ticker