docs: 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))