class_docstr: Base class for file handler calibration tests.
class_docstr_tok: ["Base","class","for","file","handler","calibration","tests","."]
docstr: Provide fake image counts.
docstr_tok: ["Provide","fake","image","counts","."]
code: def counts(self):
      """Provide fake image counts."""
      return xr.DataArray([[0, 10], [100, 255]], dims=("y", "x"))
  
imports: import unittest
  from datetime import datetime
  import numpy
  import pytest
  import xarray
  from satpy.readers.seviri_base import SEVIRICalibrationAlgorithm, SEVIRICalibrationHandler
label_desc: Use image node_id 1 for calling the TestFileHandlerCalibrationBase obj's underlying member method code with example usage: obj.counts() and returns: xr