'Query or modify the options of the specific tab_id.
If kw is not given, returns a dict of the tab option values. If option
is specified, returns the value of that option. Otherwise, sets the
options to the corresponding values.'

def tab(self, tab_id, option=None, **kw):

    if (option is not None):
        kw[option] = None
    return _val_or_dict(kw, self.tk.call, self._w, 'tab', tab_id)
