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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 status(self, name=''):
 """Return a list containing a single service's info if `name` is supplied, else returns a list of all services' info. """

        logger.warn(
            'Note that `status` is currently not so robust and may break on '
            'different systems')
        init = self._get_implementation(name)
        if name:
            self._assert_service_installed(init, name)
        logger.info('Retrieving status...')
        return init.status(name)