code: def _create_cmip_dataset(data_variable: str = "HT"):
      proj = xr.DataArray(
          [],
          attrs={
              "semi_major_axis": 1.0,
              "semi_minor_axis": 1.0,
              "perspective_point_height": 1.0,
              "longitude_of_projection_origin": -90.0,
              "sweep_angle_axis": "x",
          },
      )
      x__ = xr.DataArray(
          [0, 1],
          attrs={"scale_factor": 2.0, "add_offset": -1.0},
          dims=("x",),
      )
      y__ = xr.DataArray(
          [0, 1],
          attrs={"scale_factor": -2.0, "add_offset": 1.0},
          dims=("y",),
      )
  
      ht_da = xr.DataArray(
          np.array([2, -1, -32768, 32767])
          .astype(np.int16)
          .reshape((2, 2)),
          dims=("y", "x"),
          attrs={
              "scale_factor": 0.3052037,
              "add_offset": 0.0,
              "_FillValue": np.array(-1).astype(np.int16),
              "_Unsigned": "True",
              "units": "m",
          },
      )
  
      fake_dataset = xr.Dataset(
          data_vars={
              "goes_imager_projection": proj,
              "x": x__,
              "y": y__,
              data_variable: ht_da,
              "nominal_satellite_subpoint_lat": np.array(0.0),
              "nominal_satellite_subpoint_lon": np.array(-89.5),
              "nominal_satellite_height": np.array(35786.02),
              "spatial_resolution": "10km at nadir",
          },
          attrs={
              "time_coverage_start": "2017-09-20T17:30:40.8Z",
              "time_coverage_end": "2017-09-20T17:41:17.5Z",
              "spatial_resolution": "2km at nadir",
          },
      )
      return fake_dataset
  
imports: import contextlib
  from typing import Optional
  from unittest import mock
  import numpy
  import pytest
  import xarray
label_desc: Use image node_id 1 for calling a global function with example usage: _create_cmip_dataset(data_variable) and returns: fake_dataset