code: def calculate_normalized_ratios(ratios, ch_medians, channels):
      
      outratios = []
      for quant in ratios:
          quant.update({ch: str(quant[ch] / ch_medians[ch])
                        if quant[ch] != 'NA' else 'NA' for ch in channels})
          outratios.append(quant)
      return outratios
docs: Calculates ratios for PSM tables containing isobaric channels with
      raw intensities. Normalizes the ratios by median. NA values or values
      below min_intensity are excluded from the normalization.