Update app.py

app.py

@@ -18,6 +18,11 @@ from langchain.chat_models import ChatOpenAI
 # set this key as an environment variable
 os.environ["HUGGINGFACEHUB_API_TOKEN"] = st.secrets['Key2']
 os.environ["OPENAI_API_KEY"] =st.secrets['Key3']
+from langchain.llms import LlamaCpp
+from langchain import PromptTemplate, LLMChain
+from langchain.callbacks.manager import CallbackManager
+from langchain.callbacks.streaming_stdout import StreamingStdOutCallbackHandler
+
 ###########################################################################################
 
 def get_pdf_text(pdf_docs : list) -> str: