Style corrections

InvenTree/part/models.py

@@ -343,7 +343,6 @@ class Part(MPTTModel):
         # No serial numbers found
         return 0
 
-
     def getNextSerialNumber(self):
         """
         Return the next-available serial number for this Part.
@@ -356,7 +355,6 @@ class Part(MPTTModel):
         else:
             return int(n) + 1
 
-
     def getSerialNumberString(self, quantity):
         """
         Return a formatted string representing the next available serial numbers,

InvenTree/stock/tests.py

@@ -392,7 +392,7 @@ class VariantTest(StockTest):
             item.save()
 
         # Verify items with a non-numeric serial don't offer a next serial.
-        item.serial="string"
+        item.serial = "string"
         item.save()
         self.assertEqual(variant.getNextSerialNumber(), None)