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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_context_data(self, **kwargs):
 """ Populate the context of the template with all published entries and all the categories. """

        context = super(Sitemap, self).get_context_data(**kwargs)
        context.update(
            {'entries': Entry.published.all(),
             'categories': Category.published.all(),
             'authors': Author.published.all()}
        )
        return context