Fix mllama monkey patch tests (#737)

## Summary
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this proposed code change. --->
With transformers >= 4.52.0, there was some refactoring of mllama model
code.
 
Fixing part of #729
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## Details
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should be aware of?
--->

## Testing Done
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tested. --->
 Gemma3 monkey patch tests pass
```
pytest test/transformers/test_monkey_patch.py::test_apply_liger_kernel_to_instance_for_mllama_for_conditional_generation
pytest test/transformers/test_monkey_patch.py::test_apply_liger_kernel_to_instance_for_mllama_for_causal_lm
```
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---------

Co-authored-by: Shao Tang <[email protected]>
Co-authored-by: Vaibhav Jindal <[email protected]>

Author: 3 people

src/liger_kernel/transformers/monkey_patch.py

@@ -428,13 +428,14 @@ def apply_liger_kernel_to_mllama(
         if isinstance(model, MllamaForConditionalGeneration):
             language_model: MllamaForCausalLM = model.language_model
             vision_model: MllamaVisionModel = model.vision_model
-            text_model: MllamaTextModel = language_model.model
+            text_model: MllamaTextModel = language_model
         elif isinstance(model, MllamaForCausalLM):
             text_model = model.model
             vision_model = None
         elif isinstance(model, MllamaTextModel):
             text_model = model
             vision_model = None
+
         else:
             raise ValueError(f"Unsupported Mllama model type: {type(model)}")
 

test/transformers/test_monkey_patch.py

@@ -348,10 +348,10 @@ def test_apply_liger_kernel_to_instance_for_mllama_for_conditional_generation():
         assert isinstance(dummy_model_instance, MllamaForConditionalGeneration)
 
         # Check that model instance variables are not yet patched with Liger modules
-        assert inspect.getsource(dummy_model_instance.language_model.model.norm.forward) != inspect.getsource(
+        assert inspect.getsource(dummy_model_instance.language_model.norm.forward) != inspect.getsource(
             LigerRMSNorm.forward
         )
-        for layer in dummy_model_instance.language_model.model.layers:
+        for layer in dummy_model_instance.language_model.layers:
             assert inspect.getsource(layer.mlp.forward) != inspect.getsource(LigerSwiGLUMLP.forward)
             assert inspect.getsource(layer.input_layernorm.forward) != inspect.getsource(LigerRMSNorm.forward)
             assert inspect.getsource(layer.post_attention_layernorm.forward) != inspect.getsource(LigerRMSNorm.forward)
@@ -377,10 +377,10 @@ def test_apply_liger_kernel_to_instance_for_mllama_for_conditional_generation():
         _apply_liger_kernel_to_instance(model=dummy_model_instance)
 
         # Check that the model's instance variables were correctly patched with Liger modules
-        assert inspect.getsource(dummy_model_instance.language_model.model.norm.forward) == inspect.getsource(
+        assert inspect.getsource(dummy_model_instance.language_model.norm.forward) == inspect.getsource(
             LigerRMSNorm.forward
         )
-        for layer in dummy_model_instance.language_model.model.layers:
+        for layer in dummy_model_instance.language_model.layers:
             assert inspect.getsource(layer.mlp.forward) == inspect.getsource(LigerSwiGLUMLP.forward)
             assert inspect.getsource(layer.input_layernorm.forward) == inspect.getsource(LigerRMSNorm.forward)
             assert inspect.getsource(layer.post_attention_layernorm.forward) == inspect.getsource(LigerRMSNorm.forward)