Update pages/1_Python.py

pages/1_Python.py

@@ -5,6 +5,8 @@ from langchain_core.messages import HumanMessage, SystemMessage
 
 # Load HuggingFace token from environment variable
 hf = os.getenv('Data_science')
+if hf is None:
+    raise ValueError("Hugging Face token not found. Please set the 'Data_science' environment variable.")
 os.environ['HUGGINGFACEHUB_API_TOKEN'] = hf
 os.environ['HF_TOKEN'] = hf