class_docstr: HRV filehandler.
docstr: Get dataset from file.
code: def get_dataset(self, dataset_id, dataset_info):
      """Get dataset from file."""
      return NotImplementedError(
          "Currently the HRV channel is not implemented."
      )
  
imports: import datetime
  import logging
  from datetime import timedelta
  import numpy
  from satpy._compat import cached_property
  from satpy.readers._geos_area import get_area_definition, get_geos_area_naming
  from satpy.readers.eum_base import get_service_mode
  from satpy.readers.file_handlers import BaseFileHandler, open_dataset
  from satpy.readers.seviri_base import CHANNEL_NAMES, SATNUM, NoValidOrbitParams, OrbitPolynomialFinder, SEVIRICalibrationHandler, add_scanline_acq_time, get_cds_time, get_satpos, mask_bad_quality, round_nom_time
  from satpy.utils import get_legacy_chunk_size
label_desc: Use image node_id 1 for calling the NCSEVIRIHRVFileHandler obj's underlying member method code with example usage: obj.get_dataset(dataset_id, dataset_info) and returns: NotImplementedError