code: def fake_dataset(start_time_str):
      """Create a CLAAS-like test dataset."""
      cph = xr.DataArray([[[0, 1], [2, 0]]], dims=("time", "y", "x"))
      ctt = xr.DataArray([[280, 290], [300, 310]], dims=("y", "x"))
      time_bounds = xr.DataArray(
          [[12436.91666667, 12436.92534722]], dims=("time", "bndsize")
      )
      attrs = {
          "CMSAF_proj4_params": "+a=6378169.0 +h=35785831.0 "
          "+b=6356583.8 +lon_0=0 +proj=geos",
          "CMSAF_area_extent": np.array(
              [
                  -5456233.41938636,
                  -5453233.01608472,
                  5453233.01608472,
                  5456233.41938636,
              ]
          ),
          "time_coverage_start": start_time_str,
          "time_coverage_end": "2085-08-13T13:15:00Z",
      }
      return xr.Dataset(
          {"cph": cph, "ctt": ctt, "time_bnds": time_bounds},
          attrs=attrs,
      )
  
imports: import datetime
  import os
  import numpy
  import pytest
  import xarray
  from pyresample.geometry import AreaDefinition
  from satpy.tests.utils import make_dataid
label_desc: Use image node_id 3 for calling a global function with example usage: fake_dataset(start_time_str) and returns: xr