Update app.py

app.py

@@ -7,7 +7,7 @@ from langchain_openai import OpenAIEmbeddings, ChatOpenAI
 from langchain_core.prompts import PromptTemplate
 from langchain.chains import RetrievalQA
 from ragatouille import RAGPretrainedModel
-from langchain.document_loaders import PyPDFLoader
+from langchain_community.document_loaders import PyPDFLoader
 
 RAG = RAGPretrainedModel.from_pretrained("colbert-ir/colbertv2.0")