Duplicate check for size.

bikeshop_project/bike/models.py

@@ -72,7 +72,7 @@ class Bike(models.Model):
 
     def can_assessed(self):
         return self.colour is not None and self.make is not None and self.size is not None and self.source is not None \
-               and self.price is not None and self.size is not None
+               and self.price is not None
 
     def can_available(self):
         return self.stolen is not None and self.cpic_searched_at is not None and self.serial_number is not None