code: def find_coefficient_index(sensor, wavelength_range, resolution=0):
      
  
      index_map = COEFF_INDEX_MAP[sensor.lower()]
      # Find the best resolution of coefficients
      for res in sorted(index_map.keys()):
          if resolution <= res:
              index_map = index_map[res]
              break
      else:
          raise ValueError("Unrecognized data resolution: {}", resolution)
      # Find the best wavelength of coefficients
      if isinstance(wavelength_range, str):
          # wavelength range is actually a band name
          return index_map[wavelength_range]
      else:
          for k, v in index_map.items():
              if isinstance(k, str):
                  # we are analyzing wavelengths and ignoring dataset names
                  continue
              if k[0] <= wavelength_range[1] <= k[2]:
                  return v
docs: Return index in to coefficient arrays for this band's wavelength.
  
      This function search through the `COEFF_INDEX_MAP` dictionary and
      finds the first key where the nominal wavelength of `wavelength_range`
      falls between the minimum wavelength and maximum wavelength of the key.
      `wavelength_range` can also be the standard name of the band. For
      example, "M05" for VIIRS or "1" for MODIS.
  
      :param sensor: sensor of band to be corrected
      :param wavelength_range: 3-element tuple of (min wavelength, nominal wavelength, max wavelength)
      :param resolution: resolution of the band to be corrected
      :return: index in to coefficient arrays like `aH2O`, `aO3`, etc.
               None is returned if no matching wavelength is found