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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 reqHistogramData( self, contract: Contract, useRTH: bool, period: str) -> List[HistogramData]: """ Request histogram data. This method is blocking. https://interactivebrokers.github.io/tws-api/histograms.html Args: contract: Contract to query. useRTH: If True then only show data from within Regular Trading Hours, if False then show all data. period: Period of which data is being requested, for example '3 days'. """

        return self._run(
            self.reqHistogramDataAsync(contract, useRTH, period))