Update app.py

app.py

@@ -1,10 +1,14 @@
 import gradio as gr
 from transformers import LlamaForCausalLM, LlamaTokenizer
 import torch
+import os
 
 # Define model name and local directory
 local_model_dir = "./chameleon-7b"
 
+# Verify that the directory contains necessary files
+assert os.path.exists(local_model_dir), f"{local_model_dir} does not exist"
+
 # Load the model and tokenizer from the local directory
 tokenizer = LlamaTokenizer.from_pretrained(local_model_dir)
 model = LlamaForCausalLM.from_pretrained(local_model_dir)