typo on encode_image()

app.py

@@ -133,7 +133,7 @@ chat_mode = {}
 
 def encode_image(image_path):
     with open(image_path, "rb") as image_file:
-        return base64.v64encode(image_file.read()).decode('utf-8')
+        return base64.b64encode(image_file.read()).decode('utf-8')
 
 def generation(message, history):
     """