How to use tensorflow is a QACHAIN

chain = RetrievalQAWithSourcesChain.from_llm(llm=llm, retriever=vectorstore.as_retriever(),max_tokens_limit=1024,return_source_documents=True)

query=input("Prompt: ")

print(‘query accepted’)

result=chain({‘question’:query})

ERROR:
<module ‘torch’ from ‘C:\Users\saxen\AppData\Local\Programs\Python\Python311\Lib\site-packages\torch\init.py’> is not a valid TensorType, please select one of [‘pt’, ‘tf’, ‘np’, ‘jax’]