app.py

import streamlit as st
import langcodes

# https://huggingface.co/blog/streamlit-spaces
langtext = st.text_area("language code", "en")
found = langcodes.find(langtext)
display = found.display_name()

if langcodes.tag_is_valid('langtext'):
  st.write(f"'{langtext}' is a valid BCP-47 language code")  
else:
  st.write(f"'{langtext}' is not a valid BCP-47 language code")  

st.write(f"langcodes found the following tag: {found}")
st.write(f"Display name: {display}")