Add error check to createdefaultadmin command

webapp/management/commands/createdefaultadmin.py

@@ -7,6 +7,10 @@ class Command(BaseCommand):
     password = "password123"
 
     def handle(self, *args, **options):
+        if User.objects.filter(username=self.user_name).exists():
+            self.stdout.write("Default admin already exists. Skipping.")
+            return
+
         u = User(username=self.user_name)
         u.set_password(self.password)
         u.is_superuser = True