Let evaluator name to be a string

Handle case were self.inference_engine.get_engine_id() is not implemented

Signed-off-by: Martín Santillán Cooper <[email protected]>

Author: martinscooper

src/unitxt/llm_as_judge.py

@@ -57,7 +57,7 @@ class LLMJudge(BulkInstanceMetric):
     # option_selection_strategy: OptionSelectionStrategyEnum = (
     #     OptionSelectionStrategyEnum.PARSE_OUTPUT_TEXT
     # )
-    evaluator_name: EvaluatorNameEnum = None
+    evaluator_name: Optional[Union[str,EvaluatorNameEnum]] = None
     check_positional_bias: bool = True
     context_fields: Union[str, List[str], Dict[str, str]] = ["context"]
     generate_summaries: bool = True
@@ -77,9 +77,10 @@ def prepare(self):
             }
 
         if self.evaluator_name is None:
-            self.evaluator_name = self.inference_engine.get_engine_id()
-        elif not isinstance(self.evaluator_name, EvaluatorNameEnum):
-            self.evaluator_name = EvaluatorNameEnum[self.evaluator_name]
+            try:
+                self.evaluator_name = self.inference_engine.get_engine_id()
+            except NotImplementedError:
+                self.evaluator_name = "not_set"
 
     def before_process_multi_stream(self):
         super().before_process_multi_stream()