fix

moto/elb/responses.py

@@ -241,8 +241,11 @@ class ELBResponse(BaseResponse):
                         elif t_key.split('.')[3] == 'Value':
                             tag_values.extend(t_val)
 
-                counts = sorted({i:tag_keys.count(i) for i in tag_keys}.items(),
-                                key=lambda i:i[1], reverse=True) 
+                counts = {}
+                for i in tag_keys:
+                    counts[i] = tag_keys.count(i)
+
+                counts = sorted(counts.items(), key=lambda i:i[1], reverse=True) 
 
                 if counts and counts[0][1] > 1:
                     # We have dupes...