Fixes to various issues reported by pyflakes

Pyflake is a python (2) source checker. This patch fixes various
(mostly trivial) errors and warnings it reports.

Change-Id: Ia35c5ac61751b927814cf693994c632c412386ea

rest-api-templates/transform.py

@@ -52,7 +52,6 @@ class Transform(object):
         dest_exists = os.path.exists(dest_file)
         if dest_exists and not self.overwrite:
             return
-        tmp_file = tempfile.mkstemp()
         with tempfile.NamedTemporaryFile() as out:
             out.write(renderer.render(self.template, model))
             out.flush()