app.py

import streamlit as st
import langcodes

# https://huggingface.co/blog/streamlit-spaces
langtext = st.text_input("language code", "en")

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

try:
  lang = langcodes.Language.get(langtext)
except LanguageTagError as e: 
  st.write(f"{e}")
  lang = None
  



if lang:
  st.write(f"'{lang}' is a valid BCP-47 language code")    
else:
  try:
    found = langcodes.find(langtext)
    lang = found
  except LookupError as e:
    st.write(f"Couldn't look up langtext, sorry: {e}")
    lang = None
  

#st.write(f"langcodes found the following tag: {type(found)}") # a Language object
display = lang.display_name()

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