class_docstr: AHI gridded format reader.
  
  This data is flat binary, big endian unsigned short.
  It covers the region 85E -> 205E, 60N -> 60S at variable resolution:
  - 0.005 degrees for Band 3
  - 0.01 degrees for Bands 1, 2 and 4
  - 0.02 degrees for all other bands.
  These are approximately equivalent to 0.5, 1 and 2km.
  
  Files can either be zipped with bz2 compression (like the HSD format
  data), or can be uncompressed flat binary.
docstr: Initialize the reader.
docstr_tok: ["Initialize","the","reader","."]
code: def __init__(self, filename, filename_info, filetype_info):
      """Initialize the reader."""
      super(AHIGriddedFileHandler, self).__init__(
          filename, filename_info, filetype_info
      )
      self._unzipped = unzip_file(self.filename)
      # Assume file is not zipped
      if self._unzipped:
          # But if it is, set the filename to point to unzipped temp file
          self.filename = self._unzipped
      # Get the band name, needed for finding area and dimensions
      self.product_name = filetype_info["file_type"]
      self.areaname = filename_info["area"]
      self.sensor = "ahi"
      self.res = AHI_CHANNEL_RES[self.product_name[:3]]
      if self.areaname == "fld":
          self.nlines = AHI_FULLDISK_SIZES[self.res]["y_size"]
          self.ncols = AHI_FULLDISK_SIZES[self.res]["x_size"]
      else:
          raise NotImplementedError("Only full disk data is supported.")
  
      # Set up directory path for the LUTs
      app_dirs = AppDirs("ahi_gridded_luts", "satpy", "1.0.2")
      self.lut_dir = os.path.expanduser(app_dirs.user_data_dir) + "/"
      self.area = None
  
imports: import logging
  import os
  import dask.array
  import numpy
  import xarray
  from appdirs import AppDirs
  from pyresample import geometry
  from satpy.readers.file_handlers import BaseFileHandler
  from satpy.readers.utils import unzip_file
  from satpy.utils import get_legacy_chunk_size
label_desc: Use image node_id 1 to create a new AHIGriddedFileHandler object from inherited base classes: BaseFileHandler with example: obj = AHIGriddedFileHandler(filename, filename_info, filetype_info)