fix: download button

app.py

@@ -8,6 +8,12 @@ st.markdown("Users can load their time-series data and select a set of transform
  Go ahead and use the sidebar on the left to upload your data files in *.json* format and start exploring and transforming it!")
 col1, col2 = st.columns(2)
 
+
+@st.experimental_memo
+def convert_df(df):
+   return df.to_csv(index=False).encode('utf-8')
+
+
 file_names, file_bytes = [], []
 with st.sidebar:
     files = st.file_uploader("Load files", accept_multiple_files = True)
@@ -87,8 +93,16 @@ with col2:
                 df_right[relative_key] = [[field_value - baseline_mean[i] for field_value in df_right[option[0]][i]] for i in range(len(df_right))]
                 st.markdown("After adding calculated fields")
                 st.dataframe(df_right)
-                st.download_button('Download CSV', df_right.to_csv("myfile.csv"))
-                st.info("Your data has been downloaded, you can visualize and detect outliers in the 'Plotting' and 'Detect Outliers' pages on the sidebar.")
+                csv = convert_df(df_right)
+                downl = st.download_button(
+                   "Press to Download CSV",
+                   csv,
+                   "file.csv",
+                   "text/csv",
+                   key='download-csv'
+                )
+                if downl:
+                    st.info("Your data has been downloaded, you can visualize and detect outliers in the 'Plotting' and 'Detect Outliers' pages on the sidebar.")
 
 if not df_base.empty:
     st.warning("Consider running outlier detection to clean your data!", icon="⚠️")