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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_absolute_url(self):
 """ Returns absolute URL for the category. """

        if not self.tree_parent_id:
            url = reverse('root_homepage')
        else:
            url = reverse('category_detail', kwargs={'category' : self.tree_path})
        if self.site_id != settings.SITE_ID:
            # prepend the domain if it doesn't match current Site
            return 'http://' + self.site.domain + url
        return url