(self, item=None)
return self.tk.call(self._w, "focus", item)
If item is specified, sets the focus item to item. Otherwise,
        returns the current focus item, or '' if there is none.
If item is specified, sets the focus item to item. Otherwise,
        returns the current focus item, or '' if there is none.
If item is specified sets the focus item to item . Otherwise returns the current focus item or if there is none .
def focus(self, item=None):
        """If item is specified, sets the focus item to item. Otherwise,
        returns the current focus item, or '' if there is none."""
        return self.tk.call(self._w, "focus", item)
def focus ( self , item = None ) : return self . tk . call ( self . _w , "focus" , item )