This should work now

app.py

@@ -39,4 +39,7 @@ run_button = st.button(
 )
 
 if ims is not None:
-    cols = st.columns(n_butterflies)
+    cols = st.columns(n_butterflies)
+    for j, im in enumerate(ims):
+        i = j % n_butterflies
+        cols[i].image(im, use_column_width=True)