def __init__(self, tab_group, request=None):
        super(Tab, self).__init__()
        # Priority: constructor, class-defined, fallback
        if not self.name:
            raise ValueError("%s must have a name." % self.__class__.__name__)
        self.name = unicode(self.name)  # Force unicode.
        if not self.slug:
            raise ValueError(self.__class__.__name__ % "%s must have a slug.")
        self.tab_group = tab_group
        self.request = request
        if request:
            self._allowed = self.allowed(request)
            self._enabled = self.enabled(request)
dataset/ETHPy150Open Havate/havate-openstack/proto-build/gui/horizon/Horizon_GUI/horizon/tabs/base.py/Tab.__init__/swapped operands of `%`