good quality generation example for GPT, GPT-2, Transfo-XL, XLNet

pytorch_transformers/modeling_openai.py

@@ -214,6 +214,10 @@ class OpenAIGPTConfig(PretrainedConfig):
                 "or the path to a pretrained model config file (str)"
             )
 
+    @property
+    def max_position_embeddings(self):
+        return self.n_positions
+
     @property
     def hidden_size(self):
         return self.n_embd