add message about speed

app.py

@@ -26,6 +26,7 @@ agent.run("Draw me a picture a river and some trees.")
 )
 
 st.subheader("Try out the tool below!")
+st.markdown("Note that the first run may be slow as it downloads files needed inference. Furthermore, the text-2-image model itself will be running on CPU. After the first run, it should be faster!")
 
 api_key = st.text_input('OpenAI API key')