def on_cleanup_error(function, path, excinfo):
                click.secho("warning: failed to remove file or directory: {}\n"
                            "please delete it manually.".format(path),
                            fg="red")
def on_lower_bound_checked_changed(self):
        if self.ui.checkBoxLowerBound.isChecked():
            self.ui.spinBoxLowerBound.setEnabled(True)
            self.ui.spinBoxBoundaryNumber.setEnabled(True)
        elif not self.ui.checkBoxUpperBound.isChecked():
            self.ui.spinBoxLowerBound.setEnabled(False)
            self.ui.spinBoxBoundaryNumber.setEnabled(False)
        else:
            self.ui.spinBoxLowerBound.setEnabled(False)