Fix non-consequential typo
@@ -216,7 +216,7 @@ class X11Handler(BaseX11Handler):
raise RuntimeError("Couldn't determine how to connect to local X "
"server, DISPLAY is %s" % (
repr(os.environ['DISPLAY'])
- if 'DISPLAY' is os.environ
+ if 'DISPLAY' in os.environ
else 'not set'))
@classmethod
