fix deprecated functions

app.py

@@ -6,13 +6,19 @@ __all__ = ['hub_llm', 'title', 'description', 'combine_prompt_template', 'pdf_ex
            'chunk_overlap_input', 'examples', 'outputs', 'iface', 'summarize']
 
 # %% ../drive/MyDrive/Codici/Python/Apps/Gradio_App/Langchain_apps/langchain_summarization_app.ipynb 3
-from langchain import HuggingFaceHub, PromptTemplate, LLMChain
+from langchain_community.llms import HuggingFaceHub
+from langchain_community.document_loaders import PyPDFLoader
+from langchain_core.prompts import PromptTemplate
+from langchain.chains import LLMChain
 from langchain.text_splitter import CharacterTextSplitter
 from langchain.chains.mapreduce import MapReduceChain
 from langchain.prompts import PromptTemplate
 from langchain.docstore.document import Document
 from langchain.chains.summarize import load_summarize_chain
-from langchain.document_loaders import PyPDFLoader
+
+import dotenv
+from dotenv import load_dotenv
+load_dotenv()
 
 # %% ../drive/MyDrive/Codici/Python/Apps/Gradio_App/Langchain_apps/langchain_summarization_app.ipynb 5
 hub_llm = HuggingFaceHub(