Closes #9414: Add clone() method to NetBoxModel for copying instance attributes

docs/plugins/development/models.md

@@ -49,6 +49,24 @@ class MyModel(NetBoxModel):
     ...
 ```
 
+### The `clone()` Method
+
+!!! info
+    This method was introduced in NetBox v3.3.
+
+The `NetBoxModel` class includes a `clone()` method to be used for gathering attriubtes which can be used to create a "cloned" instance. This is used primarily for form initialization, e.g. when using the "clone" button in the NetBox UI. By default, this method will replicate any fields listed in the model's `clone_fields` list, if defined.
+
+Plugin models can leverage this method by defining `clone_fields` as a list of field names to be replicated, or override this method to replace or extend its content:
+
+```python
+class MyModel(NetBoxModel):
+
+    def clone(self):
+        attrs = super().clone()
+        attrs['extra-value'] = 123
+        return attrs
+```
+
 ### Enabling Features Individually
 
 If you prefer instead to enable only a subset of these features for a plugin model, NetBox provides a discrete "mix-in" class for each feature. You can subclass each of these individually when defining your model. (Your model will also need to inherit from Django's built-in `Model` class.)