docstr: Test using all fields as identifier keys.
code: def test_all_identifiers(self):
      """Test using all fields as identifier keys."""
      model = static_preds.StaticPredictions(
          self.input_ds,
          self.preds_ds,
          input_identifier_keys=["name", "val"],
      )
      self.assertEqual(self.input_ds.spec(), model.input_spec())
      self.assertEqual(self.preds_ds.spec(), model.output_spec())
      # Test on whole dataset
      self.assertEqual(
          list(model.predict(self.input_ds.examples)),
          list(self.preds_ds.examples),
      )
      # Test on a slice
      self.assertEqual(
          list(model.predict(self.input_ds.examples[2:5])),
          list(self.preds_ds.examples[2:5]),
      )
      # Test on unknown examples
      with self.assertRaises(KeyError):
          # Should raise an exception on the second input.
          inputs = [
              {"name": "nine", "val": 9},
              {"name": "twenty", "val": 20},
          ]
          # Use list() to force the generator to run.
          _ = list(model.predict(inputs))
  
file_path: lit/lit_nlp/components/static_preds_test.py
imports: from absl.testing import absltest
  from lit_nlp.api import dataset
  from lit_nlp.api import types
  from lit_nlp.components import static_preds
label_desc: Use image node_id 2 for calling the StaticPredictionsTest obj's underlying member method code with example usage: obj.test_all_identifiers() without return types