Updates the attribute toolbar

        Parameters
        ----------
        key: 3-tuple of Integer, defaults to current cell
        \tCell to which attributes the attributes toolbar is updated

def update_attribute_toolbar(self, key=None):
        """Updates the attribute toolbar

        Parameters
        ----------
        key: 3-tuple of Integer, defaults to current cell
        \tCell to which attributes the attributes toolbar is updated

        """

        if key is None:
            key = self.actions.cursor

        post_command_event(self, self.ToolbarUpdateMsg, key=key,
                           attr=self.code_array.cell_attributes[key])