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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 _create_actions(self):
 """ Create associated actions """

        self.action_to_lower = QtWidgets.QAction(self.editor)
        self.action_to_lower.triggered.connect(self.to_lower)
        self.action_to_upper = QtWidgets.QAction(self.editor)
        self.action_to_upper.triggered.connect(self.to_upper)
        self.action_to_lower.setText(_('Convert to lower case'))
        self.action_to_lower.setShortcut('Ctrl+U')
        self.action_to_upper.setText(_('Convert to UPPER CASE'))
        self.action_to_upper.setShortcut('Ctrl+Shift+U')
        self.menu = QtWidgets.QMenu(_('Case'), self.editor)
        self.menu.addAction(self.action_to_lower)
        self.menu.addAction(self.action_to_upper)
        self._actions_created = True