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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 on_install(self, editor):
 """ Add the folding menu to the editor, on install. :param editor: editor instance on which the mode has been installed to. """

        super(FoldingPanel, self).on_install(editor)
        self.context_menu = QtWidgets.QMenu(_('Folding'), self.editor)
        action = self.action_collapse = QtWidgets.QAction(
            _('Collapse'), self.context_menu)
        action.setShortcut('Shift+-')
        action.triggered.connect(self._on_action_toggle)
        self.context_menu.addAction(action)
        action = self.action_expand = QtWidgets.QAction(_('Expand'),
                                                        self.context_menu)
        action.setShortcut('Shift++')
        action.triggered.connect(self._on_action_toggle)
        self.context_menu.addAction(action)
        self.context_menu.addSeparator()
        action = self.action_collapse_all = QtWidgets.QAction(
            _('Collapse all'), self.context_menu)
        action.setShortcut('Ctrl+Shift+-')
        action.triggered.connect(self._on_action_collapse_all_triggered)
        self.context_menu.addAction(action)
        action = self.action_expand_all = QtWidgets.QAction(
            _('Expand all'), self.context_menu)
        action.setShortcut('Ctrl+Shift++')
        action.triggered.connect(self._on_action_expand_all_triggered)
        self.context_menu.addAction(action)
        self.editor.add_menu(self.context_menu)