Fix missed in traitlets API overhaul

Closes gh-1649
10 years ago · c80c19be0d
parent 1816b306cb
commit c80c19be0d
1 changed files with 1 additions and 1 deletions
--- a/notebook/notebookapp.py
+++ b/notebook/notebookapp.py
@ -844,7 +844,7 @@ class NotebookApp(JupyterApp):
    @observe('pylab')
    def _update_pylab(self, change):
        """when --pylab is specified, display a warning and exit"""
-        if new != 'warn':
+        if change['new'] != 'warn':
            backend = ' %s' % change['new']
        else:
            backend = ''