diff --git a/prompt_tuner.py b/prompt_tuner.py
index 99320861..1ce3e210 100644
--- a/prompt_tuner.py
+++ b/prompt_tuner.py
@@ -78,8 +78,10 @@ class UniversalPromptTuningMixin:
             Embedding.__call__ = old_embedding_call
 
 for k in dir(GPTPromptTuningMixin):
-    if not hasattr(UniversalPromptTuningMixin, k):
-        setattr(UniversalPromptTuningMixin, k, getattr(GPTPromptTuningMixin, k))
+    v = getattr(GPTPromptTuningMixin, k)
+    _v = getattr(UniversalPromptTuningMixin, k, None)
+    if _v is None or (_v is getattr(object, k, None) and callable(_v) and not isinstance(_v, type)):
+        setattr(UniversalPromptTuningMixin, k, v)
 
 
 class AutoPromptTuningLM(UniversalPromptTuningMixin, transformers.AutoModelForCausalLM):