minor improvements

src/scenic/core/errors.py

@@ -1,5 +1,6 @@
 """Common exceptions and error handling."""
 
+import importlib
 import itertools
 import pathlib
 import traceback
@@ -26,7 +27,8 @@
 hiddenFolders = [
     pathlib.Path(scenic.core.__file__).parent,      # scenic.core submodules
     pathlib.Path(scenic.syntax.__file__).parent,    # scenic.syntax submodules
-    '<frozen importlib._bootstrap>',
+    '<frozen importlib._bootstrap>',                # parts of importlib used internally
+    pathlib.Path(importlib.__file__).parent,
 ]
 
 ## Exceptions

src/scenic/simulators/carla/behaviors.scenic

@@ -1,7 +1,6 @@
 """Behaviors for dynamic agents in CARLA scenarios."""
 
 from scenic.domains.driving.behaviors import *	# use common driving behaviors
-import scenic.domains.driving.model as _model
 
 try:
     from scenic.simulators.carla.actions import *

src/scenic/syntax/veneer.py

@@ -446,8 +446,11 @@ def model(namespace, modelName):
 	try:
 		loadingModel = True
 		module = importlib.import_module(modelName)
-	except ModuleNotFoundError:
-		raise InvalidScenarioError(f'could not import world model {modelName}') from None
+	except ModuleNotFoundError as e:
+		if e.name == modelName:
+			raise InvalidScenarioError(f'could not import world model {modelName}') from None
+		else:
+			raise
 	finally:
 		loadingModel = False
 	names = module.__dict__.get('__all__', None)