text: #!/usr/bin/env python
  """Example process file."""
  
  
  def execute(mp):
      """User defined process."""
      # Reading and writing data works like this:
      with mp.open("file1") as raster_file:
          if raster_file.is_empty():
              return "empty"
              # This assures a transparent tile instead of a pink error tile
              # is returned when using mapchete serve.
          dem = raster_file.read(resampling="bilinear")
      return mp.hillshade(dem).astype("uint8")
  