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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(self):
 """Update the display of button after querying data from interface"""

        self.clear()
        self._set_boutons_communs()
        if self.interface:
            self.addSeparator()
            l_actions = self.interface.get_actions_toolbar()
            self._set_boutons_interface(l_actions)