Correct undefined variable in example

`model_wiz` was undefined and presumably should simply be `model`.

README.md

@@ -43,7 +43,7 @@ prompt_template=("A chat between a curious user and an artificial intelligence a
 inputs = tokenizer(
     prompt_template.format(prompt="What is 1+1?"), 
     return_tensors="pt", return_attention_mask=False).to('cuda')
-outputs = model_wiz.generate(
+outputs = model.generate(
     **inputs, max_length=200, 
     do_sample=True, 
     temperature=0.5,