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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 update_url(self, url=None):
 """ Accepts a fully-qualified url. Returns True if successful, False if not successful. """

        if not url:
            raise ValueError("Neither a url or regex was provided to update_url.")
        post_url = "%s%s" % (self.BASE_URL, url)
        r = self.session.post(post_url)
        return int(r.status_code) < 500