Patch #1696.  Don't attempt to close None in dry-run mode.
diff --git a/Lib/distutils/command/build_scripts.py b/Lib/distutils/command/build_scripts.py
index b4810c3..6af363b 100644
--- a/Lib/distutils/command/build_scripts.py
+++ b/Lib/distutils/command/build_scripts.py
@@ -112,7 +112,8 @@
                 if f:
                     f.close()
             else:
-                f.close()
+                if f:
+                    f.close()
                 self.copy_file(script, outfile)
 
         if os.name == 'posix':