class_docstr: Reader class for FCI L2 Segmented products in NetCDF4 format.
class_docstr_tok: ["Reader","class","for","FCI","L2","Segmented","products","in","NetCDF4","format","."]
docstr: Construct the area definition.
  
  Returns:
      AreaDefinition: A pyresample AreaDefinition object containing the area definition.
docstr_tok: ["Construct","the","area","definition",".","Returns",":","AreaDefinition",":","A","pyresample","AreaDefinition","object","containing","the","area","definition","."]
code: def _construct_area_def(self, dataset_id):
      """Construct the area definition.
  
      Returns:
          AreaDefinition: A pyresample AreaDefinition object containing the area definition.
  
      """
      res = dataset_id["resolution"]
  
      area_naming_input_dict = {
          "platform_name": "mtg",
          "instrument_name": "fci",
          "resolution": res,
      }
  
      area_naming = get_geos_area_naming(
          {
              **area_naming_input_dict,
              **get_service_mode("fci", self.ssp_lon),
          }
      )
  
      # Construct area definition from standardized area definition.
      stand_area_def = get_area_def(area_naming["area_id"])
  
      if (stand_area_def.width != self.ncols) | (
          stand_area_def.height != self.nlines
      ):
          raise NotImplementedError("Unrecognised AreaDefinition.")
  
      mod_area_extent = self._modify_area_extent(
          stand_area_def.area_extent
      )
  
      area_def = geometry.AreaDefinition(
          stand_area_def.area_id,
          stand_area_def.description,
          "",
          stand_area_def.crs,
          stand_area_def.width,
          stand_area_def.height,
          mod_area_extent,
      )
  
      return area_def
  
imports: import logging
  from contextlib import suppress
  import numpy
  import xarray
  from pyresample import geometry
  from satpy._compat import cached_property
  from satpy.readers._geos_area import get_geos_area_naming, make_ext
  from satpy.readers.eum_base import get_service_mode
  from satpy.readers.file_handlers import BaseFileHandler
  from satpy.resample import get_area_def
  from satpy.utils import get_legacy_chunk_size
label_desc: Use image node_id 4 for calling the FciL2NCSegmentFileHandler obj's underlying member method code with example usage: obj._construct_area_def(dataset_id) and returns: area_def