correct type of k error

app.py

@@ -106,7 +106,7 @@ def QAQuery_p(question: str):
     global vectordb_p
     # vectordb = Chroma(persist_directory='db', embedding_function=embeddings)
     retriever = vectordb_p.as_retriever()
-    retriever.search_kwargs['k'] = os.getenv("search_kwargs_k")
+    retriever.search_kwargs['k'] = int(os.getenv("search_kwargs_k"))
     # retriever.search_kwargs['fetch_k'] = 100
 
     qa = RetrievalQA.from_chain_type(llm=chat, chain_type="stuff", retriever=retriever, return_source_documents = True)