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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 load_default(self):
        ''' Load the default config files.
            First the global config file then the user config file.
        '''
        appdir = AppDirs(self.application_name, self.application_author,
                version=self.application_version)
        file_name = os.path.join(appdir.site_data_dir, "{0}.conf".format(
                self.application_name.lower()))
        if os.path.exists(file_name):
            self.load(file_name)
        if os.name is not 'posix' or os.getuid() > 0:
            config_file = os.path.join(appdir.user_data_dir, '{0}.conf'.format(
                    self.application_name.lower()))
            if os.path.exists(config_file):
                self.load(config_file)