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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 _notify(self, title, message, expected_action=None):
 """ Notify user from external event """

        if self.editor is None:
            return
        inital_value = self.editor.save_on_focus_out
        self.editor.save_on_focus_out = False
        self._flg_notify = True
        dlg_type = (QtWidgets.QMessageBox.Yes | QtWidgets.QMessageBox.No)
        expected_action = (
            lambda *x: None) if not expected_action else expected_action
        if (self._auto_reload or QtWidgets.QMessageBox.question(
                self.editor, title, message, dlg_type,
                QtWidgets.QMessageBox.Yes) == QtWidgets.QMessageBox.Yes):
            expected_action(self.editor.file.path)
        self._update_mtime()
        self.editor.save_on_focus_out = inital_value