class_docstr: Corrected Reflectance (crefl) modifier.
  
  Uses a python rewrite of the C CREFL code written for VIIRS and MODIS.
class_docstr_tok: ["Corrected","Reflectance","(","crefl",")","modifier",".","Uses","a","python","rewrite","of","the","C","CREFL","code","written","for","VIIRS","and","MODIS","."]
code: def _get_average_elevation(self):
      if self.dem_cache_key is None:
          return
  
      LOG.debug(
          "Loading CREFL averaged elevation information from: %s",
          self.dem_cache_key,
      )
      local_filename = retrieve(self.dem_cache_key)
      avg_elevation = self._read_var_from_hdf4_file(
          local_filename, self.dem_sds
      ).astype(np.float64)
      if isinstance(avg_elevation, np.ma.MaskedArray):
          avg_elevation = avg_elevation.filled(np.nan)
      return avg_elevation
  
file_path: satpy/satpy/modifiers/_crefl.py
imports: import logging
  import warnings
  import numpy
  from satpy.aux_download import DataDownloadMixin, retrieve
  from satpy.modifiers import ModifierBase
  from satpy.modifiers.angles import get_angles
label_desc: Use image node_id 5 for calling the ReflectanceCorrector obj's underlying member method code with example usage: obj._get_average_elevation() and returns: avg_elevation