Old QComboBox & QMenu

    def addPythonVersions(self, pythonVersions):
        """
        Adding a list of Python Versions to the QComboBox and to the QMenu.
        :param pythonVersions: This can be a list or a single string.
        :return: Returns True if everything went good.
        """
        try:
            nextItemIndex = len(self.pythonVersions)
            if type(pythonVersions) is list:
                for newItem in pythonVersions:
                    self.pythonVersions.insertItem(nextItemIndex, newItem)
                    self.actionPython_Version.addAction(newItem)
            else:
                self.pythonVersions.insertItem(nextItemIndex, pythonVersions)
                self.actionPython_Version.addAction(pythonVersions)
        except Exception as ErrorCode:
            raise PythonVersionError(f'Error while adding the python versions to QComboBox:\n{ErrorCode}')
            return False
        else:
            self.pythonVersions.setCurrentIndex(0) # Setting the last Python Version as the default option.
            return True