docs: def series_resistance(self, channel, resistor_index=None):
          '''
          Parameters
          ----------
          channel : int
              Analog channel index.
          resistor_index : int, optional
              Series resistor channel index.
  
              If :data:`resistor_index` is not specified, the resistor-index from
              the current context _(i.e., the result of
              :attr:`series_resistor_index`)_ is used.
  
              Otherwise, the series-resistor is temporarily set to the value of
              :data:`resistor_index` to set the capacitance before restoring back
              to the original value.
  
              See definition of :meth:`safe_series_resistor_index_read`
              decorator.
  
          Returns
          -------
          float
              Return the current series resistance value for the specified
              channel.
          '''
          if resistor_index is None:
              resistor_index = self.series_resistor_index(channel)
          value = self._series_resistance(channel)
          try:
              if channel == 0:
                  self.calibration.R_hv[resistor_index] = value
              else:
                  self.calibration.R_fb[resistor_index] = value
          except:
              pass
          return value