Update app.py

app.py

@@ -41,6 +41,13 @@ from langchain_core.runnables import RunnableLambda, RunnableParallel, RunnableP
 from langchain.schema import Document, format_document
 from langchain_core.messages import AIMessage, HumanMessage, get_buffer_string
 
+# OutputParser
+from langchain_core.output_parsers import StrOutputParser
+
+# Chroma: vectorstore
+from langchain_community.vectorstores import Chroma
+
+# Contextual Compression
 from langchain.retrievers.document_compressors import DocumentCompressorPipeline
 from langchain.text_splitter import CharacterTextSplitter
 from langchain_community.document_transformers import EmbeddingsRedundantFilter,LongContextReorder