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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 _get_redditor_listing(subpath=''):
 """Return function to generate Redditor listings."""

    def _listing(self, sort='new', time='all', *args, **kwargs):
        """Return a get_content generator for some RedditContentObject type.

        :param sort: Specify the sort order of the results if applicable
            (one of ``'hot'``, ``'new'``, ``'top'``, ``'controversial'``).
        :param time: Specify the time-period to return submissions if
            applicable (one of ``'hour'``, ``'day'``, ``'week'``,
            ``'month'``, ``'year'``, ``'all'``).

        The additional parameters are passed directly into
        :meth:`.get_content`. Note: the `url` parameter cannot be altered.

        """
        kwargs.setdefault('params', {})
        kwargs['params'].setdefault('sort', sort)
        kwargs['params'].setdefault('t', time)
        url = urljoin(self._url, subpath)  # pylint: disable=W0212
        return self.reddit_session.get_content(url, *args, **kwargs)
    return _listing