code: def atms_fake_dataset():
      """Return fake ATMS dataset."""
      atrack = 2
      xtrack = 3
      channel = 22
      lon = np.full((atrack, xtrack), 1.0)
      lat = np.full((atrack, xtrack), 2.0)
      sat_azi = np.full((atrack, xtrack), 3.0)
      antenna_temp = np.zeros((atrack, xtrack, channel))
      for idx in range(channel):
          antenna_temp[:, :, idx] = 100 + float(idx)
      return xr.Dataset(
          data_vars={
              "antenna_temp": (
                  ("atrack", "xtrack", "channel"),
                  antenna_temp,
              ),
              "lon": (("atrack", "xtrack"), lon),
              "lat": (("atrack", "xtrack"), lat),
              "sat_azi": (("atrack", "xtrack"), sat_azi),
          },
          attrs={
              "time_coverage_start": "2000-01-02T03:04:05Z",
              "time_coverage_end": "2000-01-02T04:05:06Z",
              "platform": "JPSS-1",
              "instrument": "ATMS",
          },
      )
  
file_path: satpy/satpy/tests/reader_tests/test_atms_l1b_nc.py
imports: from datetime import datetime
  import numpy
  import pytest
  import xarray
  from satpy.readers.atms_l1b_nc import AtmsL1bNCFileHandler
label_desc: Use image node_id 3 for calling a global function with example usage: atms_fake_dataset() and returns: xr