caching some queries

app.py

@@ -34,6 +34,7 @@ things_to_test = [
 def get_bcp47_from_langcode(langtext):
   pass
 
+@st.cache
 def pull_obsolete_codes(iso_code):
   session = HTMLSession() 
   r= session.get(f"https://iso639-3.sil.org/code/{iso_code}")