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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 get_with_rtdcbase(self, col1, col2, method, dataset, viscosity=None, add_px_err=False):
 """Convenience method that extracts the metadata from RTDCBase Parameters col1: str Name of the first feature of all isoelastics (e.g. isoel[0][:,0]) col2: str Name of the second feature of all isoelastics (e.g. isoel[0][:,1]) method: str The method used to compute the isoelastics (must be one of `VALID_METHODS`). dataset: dclab.rtdc_dataset.RTDCBase The dataset from which to obtain the metadata. viscosity: float or `None` Viscosity of the medium in mPa*s. If set to `None`, the flow rate of the imported data will be used (only do this if you do not need the correct values for elastic moduli). add_px_err: bool If True, add pixelation errors according to C. Herold (2017), https://arxiv.org/abs/1704.00572 """

        cfg = dataset.config
        return self.get(col1=col1,
                        col2=col2,
                        method=method,
                        channel_width=cfg["setup"]["channel width"],
                        flow_rate=cfg["setup"]["flow rate"],
                        viscosity=viscosity,
                        add_px_err=add_px_err,
                        px_um=cfg["imaging"]["pixel size"])