diff --git a/django_nuts/loaders/__init__.py b/django_nuts/loaders/__init__.py
index cce895a..87a8dbf 100644
--- a/django_nuts/loaders/__init__.py
+++ b/django_nuts/loaders/__init__.py
@@ -88,8 +88,8 @@ def load_lau(*country_codes):
         country_codes = (key for key in data.keys() if len(key) == 2)
     for country_code in country_codes:
         sheet = data[country_code]
-        nuts = {n.code: n for n in NUTS.objects.filter(code__startswith=country_code).iterator()}
-        laus = {l.code: l for l in LAU.objects.filter(code__startswith=country_code).iterator()}
+        nuts = {n_nuts.code: n_nuts for n_nuts in NUTS.objects.filter(code__startswith=country_code).iterator()}
+        laus = {l_lau.code: l_lau for l_lau in LAU.objects.filter(code__startswith=country_code).iterator()}
         created, updated = 0, 0
         for row in sheet[1:]:
             # handle exceptions in data
diff --git a/django_nuts/loaders/cz_nuts4_lau.py b/django_nuts/loaders/cz_nuts4_lau.py
index da77509..1772d02 100644
--- a/django_nuts/loaders/cz_nuts4_lau.py
+++ b/django_nuts/loaders/cz_nuts4_lau.py
@@ -18,8 +18,8 @@ def load_cz_nuts4_lau():
     # take last sheet
     sheet = data[list(data.keys())[-1]]
 
-    nuts = {n.code: n for n in NUTS.objects.filter(code__startswith='CZ').iterator()}
-    laus = {l.code: l for l in LAU.objects.filter(code__startswith='CZ').iterator()}
+    nuts = {n_nuts.code: n_nuts for n_nuts in NUTS.objects.filter(code__startswith='CZ').iterator()}
+    laus = {l_lau.code: l_lau for l_lau in LAU.objects.filter(code__startswith='CZ').iterator()}
     nuts_created, nuts_updated, lau_created, lau_updated = 0, 0, 0, 0
     for row in sheet[2:]:
         lau_code, lau_name = row[0:2]