Improved how I update additional globals

restrictedpython_code_eval.py

@@ -343,7 +343,16 @@ def _unsafe_execute(check_program, result, timeout,
                 builtins.update(utility_builtins)
 
             exec_globals = {'__builtins__': builtins}
-            exec_globals.update(additional_globals or {})
+            
+            if additional_globals is None:
+                additional_globals = {}
+
+            for key, glob in additional_globals.items():
+                if key not in exec_globals:
+                    exec_globals[key] = glob
+                
+                else:
+                    exec_globals[key].update(glob)
 
             if allowed_imports is not None:
                 if '__import__' in exec_globals['__builtins__']: