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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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])