Add before_create_obj hook to BatchCreateMutation

graphene_django_cud/mutations/core.py

@@ -252,6 +252,10 @@ def upsert_obj(
                 Model,
             )
 
+    @classmethod
+    def before_create_obj(cls, info, input, obj):
+        return None
+
     @classmethod
     def create_obj(
         cls,
@@ -378,7 +382,7 @@ def create_obj(
             model_field_values[name + "_id"] = obj_id
 
         # Foreign keys are added, we are ready to create our object
-        obj = Model.objects.create(**model_field_values)
+        obj = Model(**model_field_values)
 
         # Handle one to one rels
         if len(one_to_one_rels) > 0:
@@ -408,7 +412,10 @@ def create_obj(
 
                 setattr(obj, name, new_value)
 
-            obj.save()
+
+        cls.before_create_obj(info, input, obj)
+
+        obj.save()
 
         # Handle extras fields
         for name, extras in many_to_many_extras.items():