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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 _getConfiguration(self):
 """ Load application configuration files. :return: <dict> """

        configDirectoryPath = os.path.join("application", "config")
        config = Config(configDirectoryPath)
        configData = config.getData()

        # setting application parameters
        reactor.suggestThreadPoolSize(
            int(configData["performance"]["threadPoolSize"])
        )

        return configData