add download button

app.py

@@ -62,7 +62,7 @@ def molecule(input_pdb):
     )
     dw_script = """
         <script type="text/javascript" >
-            function download(filename, text) /{
+            function download(filename, text) {
                 var element = document.createElement('a');
                 element.setAttribute('href', 'data:text/plain;charset=utf-8,' + encodeURIComponent(text));
                 element.setAttribute('download', filename);
@@ -73,7 +73,7 @@ def molecule(input_pdb):
                 element.click();
 
                 document.body.removeChild(element);
-                /}
+                }
         </script>
     """