diff --git a/.travis.yml b/.travis.yml
index 82bc201184..09f5fa6f2d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,7 +3,6 @@ dist: xenial
 language: python
 python:
     - 3.5
-    - 3.6
 
 addons:
     apt-packages:
diff --git a/InvenTree/part/api.py b/InvenTree/part/api.py
index e119188def..024d61a4a5 100644
--- a/InvenTree/part/api.py
+++ b/InvenTree/part/api.py
@@ -67,7 +67,6 @@ class PartDetail(DraftRUDView):
 
 class PartList(generics.ListCreateAPIView):
 
-    #queryset = Part.objects.all()
     serializer_class = PartSerializer
 
     def get_queryset(self):
@@ -86,11 +85,13 @@ class PartList(generics.ListCreateAPIView):
             if self.request.query_params.get('include_child_categories', None):
                 childs = category.getUniqueChildren()
                 for child in childs:
-                    if child == cat_id: continue
+                    # Ignore the top-level category (already filtered)
+                    if child == cat_id:
+                        continue
                     flt |= Q(category=child)
 
             return Part.objects.filter(flt)
-        
+
         # Default - return all parts
         return Part.objects.all()
 
@@ -105,7 +106,6 @@ class PartList(generics.ListCreateAPIView):
     ]
 
     filter_fields = [
-        #'category',
     ]
 
     ordering_fields = [