diff --git a/functions/classes.py b/functions/classes.py
index 9c0d9fe17a72461ab32c36697fd890dc188903ec..c910e8725aa647276a33b929dda1bef841f783ac 100644
--- a/functions/classes.py
+++ b/functions/classes.py
@@ -20,16 +20,6 @@ import copy
 # - Export als GraphViz -> Nä Semeseter
 
 
-
-class ComponentCategory(Enum):
-    BATTERY = auto()
-    MOTOR = auto()
-    FRAME = auto()
-    WHEEL = auto()
-    AXLE = auto()
-    GEAR = auto()
-
-
 class AggregationLayer(Enum):
     SYSTEM = auto()
     ASSEMBLY = auto()
@@ -195,10 +185,16 @@ def print_assembly_tree(root, level=0, is_last=False):
         print(f"{component_padding}{item}")
 
 
+def check_aggregation_hierarchy(root):
+    pass
+
+
 class KPIEncoder(json.JSONEncoder):
     def default(self, o):
         if isinstance(o, uuid.UUID):
             return "kpi-" + str(o)
-        if isinstance(o, (ComponentCategory, AggregationLayer)):
+        if isinstance(o, AggregationLayer):
             return "kpi-" + o.name
         return super().default(o)
+
+pass
\ No newline at end of file