class_docstr: Test the Scene object's `.load` method for datasets coming from a reader.
class_docstr_tok: ["Test","the","Scene","object","'s","`",".load","`","method","for","datasets","coming","from","a","reader","."]
docstr: Test loading a dataset that doesn't exist then another load.
code: def test_load_no_exist2(self):
      """Test loading a dataset that doesn't exist then another load."""
      from satpy.readers.yaml_reader import FileYAMLReader
  
      load_mock = spy_decorator(FileYAMLReader.load)
      with mock.patch.object(FileYAMLReader, "load", load_mock):
          lmock = load_mock.mock
          scene = Scene(filenames=["fake1_1.txt"], reader="fake1")
          scene.load(["ds9_fail_load"])
          loaded_ids = list(scene._datasets.keys())
          assert len(loaded_ids) == 0
          lmock.assert_called_once_with(
              {
                  make_dataid(
                      name="ds9_fail_load", wavelength=(1.0, 1.1, 1.2)
                  )
              }
          )
  
          scene.load(["ds1"])
          loaded_ids = list(scene._datasets.keys())
          assert lmock.call_count == 2
          # most recent call should have only been ds1
          lmock.assert_called_with(
              {
                  make_dataid(
                      name="ds1",
                      resolution=250,
                      calibration="reflectance",
                      modifiers=tuple(),
                  ),
              }
          )
          assert len(loaded_ids) == 1
  
imports: from unittest import mock
  import pytest
  import xarray
  from dask import array
  from satpy import Scene
  from satpy.tests.utils import make_cid, make_dataid, make_dsq, spy_decorator
label_desc: Use image node_id 1 for calling the TestLoadingReaderDatasets obj's underlying member method code with example usage: obj.test_load_no_exist2() without return types