Prevent KeyError exceptions when validating meta analysis experiment URNs.

These shouldn't arise anyway, but this avoids problems in case of some strange behavior in converting properties from camelCase to snake_case.

Author: jstone-dev

src/mavedb/view_models/score_set.py

@@ -82,8 +82,8 @@ def validate_experiment_urn(cls, v):
 
     @root_validator
     def validate_experiment_urn_required_except_for_meta_analyses(cls, values):
-        experiment_urn = values["experiment_urn"]
-        meta_analysis_source_score_set_urns = values["meta_analysis_source_score_set_urns"]
+        experiment_urn = values.get("experiment_urn")
+        meta_analysis_source_score_set_urns = values.get("meta_analysis_source_score_set_urns")
         is_meta_analysis = meta_analysis_source_score_set_urns is None or len(meta_analysis_source_score_set_urns) == 0
         if experiment_urn is None and is_meta_analysis:
             raise ValidationError("An experiment URN is required, unless your score set is a meta-analysis.")