diff -urNp file-roller-3.28.0.old/postinstall.py file-roller-3.28.0/postinstall.py
--- file-roller-3.28.0.old/postinstall.py	2018-06-06 13:50:07.196718573 +0100
+++ file-roller-3.28.0/postinstall.py	2018-06-06 13:55:42.210647307 +0100
@@ -1,4 +1,4 @@
-#!/usr/bin/env python3
+#!/usr/bin/env python
 
 import os
 import subprocess
@@ -8,19 +8,19 @@ datadir = os.path.join(prefix, 'share')
 
 # Packaging tools define DESTDIR and this isn't needed for them
 if 'DESTDIR' not in os.environ:
-    print('Updating icon cache…')
+    print('Updating icon cache')
     icon_cache_dir = os.path.join(datadir, 'icons', 'hicolor')
     if not os.path.exists(icon_cache_dir):
         os.makedirs(icon_cache_dir)
     subprocess.call(['gtk-update-icon-cache', '-qtf', icon_cache_dir])
 
-    print('Updating desktop database…')
+    print('Updating desktop database')
     desktop_database_dir = os.path.join(datadir, 'applications')
     if not os.path.exists(desktop_database_dir):
         os.makedirs(desktop_database_dir)
     subprocess.call(['update-desktop-database', '-q', desktop_database_dir])
 
-    print('Compiling GSettings schemas…')
+    print('Compiling GSettings schemas')
     schemas_dir = os.path.join(datadir, 'glib-2.0', 'schemas')
     if not os.path.exists(schemas_dir):
         os.makedirs(schemas_dir)
