def start(self): from ipyparallel.nbextension.install import install_extensions if len(self.extra_args) != 1: self.exit("Must specify 'enable' or 'disable'") action = self.extra_args[0].lower() if action == 'enable': print("Enabling IPython clusters tab") install_extensions(enable=True, user=self.user) elif action == 'disable': print("Disabling IPython clusters tab") install_extensions(enable=False, user=self.user) else: self.exit("Must specify 'enable' or 'disable', not '%s'" % action)