class_docstr: A model with unsupported output type.
code: def output_spec(self) -> lit_types.Spec:
      return {"pred": lit_types.RegressionScore(parent="label")}
  
imports: from typing import NamedTuple
  from absl.testing import absltest
  from absl.testing import parameterized
  from lit_nlp.api import dataset
  from lit_nlp.api import model
  from lit_nlp.api import types
  from lit_nlp.components import curves
  from lit_nlp.lib import caching
label_desc: Use image node_id 2 for calling the _IncompatiblePredictionTestModel obj's underlying member method code with example usage: obj.output_spec() and returns: dict