Module not found error: langchain_huggingface

Beginners
1

In my Huggingface application I have mentioned langchain-huggingface module in the requirements.txt file. Now when I import langchain_hugging face in my app it is giving module not found error. Why?
Here is the code:
app.py file:
import streamlit as st
from langchain_huggingface import HuggingFaceEndpoint

def load_answer(question):
llm = HuggingFaceEndpoint(repo_id=“mistralai/Mistral-7B-Instruct-v0.3”)

answer=llm.invoke(question)
return answer

st.set_page_config(page_title=“LangChain Demo”, page_icon=“:robot:”)
st.header(“LangChain Demo”)

def get_text():
input_text = st.text_input("You: ", key=“input”)
return input_text

user_input=get_text()
response = load_answer(user_input)

submit = st.button(‘Generate’)

#If generate button is clicked
if submit:

st.subheader("Answer:")

st.write(response)

requirements.txt file:

langchain
langchain-huggingface
streamlit
huggingface-hub