correct a typo in the code snippet

README.md

@@ -59,7 +59,7 @@ def generate(situation_narrative, role_instruction, conversation_history):
     conversation_history: the previous utterances in the conversation in a list
     """
 
-    input_text = set_input(role_narrative, role_instruction, conversation_history) 
+    input_text = set_input(situation_narrative, role_instruction, conversation_history) 
 
     inputs = tokenizer([input_text], return_tensors="pt").to(device)
     outputs = model.generate(inputs["input_ids"], max_new_tokens=128, temperature=1.0, top_p=.95, do_sample=True)