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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 deleteSettings(self, groupName=None):
 """ Deletes registry items from the persistent store. """

        groupName = groupName if groupName else self.settingsGroupName
        settings = QtCore.QSettings()
        logger.info("Deleting {} from: {}".format(groupName, settings.fileName()))
        removeSettingsGroup(groupName)