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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 item_author_link(self, item):
 """ Return the author's URL. Should not be called if self.item_author_name has returned None. """

        try:
            author_url = self.item_author.get_absolute_url()
            return self.site_url + author_url
        except NoReverseMatch:
            return self.site_url