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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 op_list_apps(self):
 """Prints out and returns a list of known applications. :rtype: list :return: list of applications """

        self.logger.info('Listing known applications ...')
        apps = self.get_apps()
        for app in apps:
            self.logger.info('Found `%s`' % app)
        else:
            self.logger.info('\nDONE. No applications found in `%s` directory.\n' % APPS_DIRNAME)
        return apps