Update app.py

app.py

@@ -1,4 +1,3 @@
-
 import streamlit as st 
 import os
 import sys
@@ -44,11 +43,14 @@ if cmd_txt and cmd_txt != "":
         save(s)
         if s.returncode!= 0: 
             st.warning(f'non-zero return: {s.returncode}', icon="⚠️")
-        st.code(s.stdout.decode())
+        if s.stdout:
+            st.code(s.stdout.decode())
+        if s.stderr:
+            st.code(s.stderr.decode())
     except Exception as inst:
         st.error(inst)
 
 
 if 'outputs' in st.session_state:
     st.caption('hint: double click on long outputs')
-    st.dataframe(st.session_state['outputs'])
+    st.dataframe(st.session_state['outputs'])