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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_abs_url(self, rel_url):
 """ Create an absolute url from a relative one. 'http://example.com:80/kml_master.kml' """

        rel_url = rel_url.lstrip("/")
        return "{}://{}:{}/{}".format(self.url_scheme, self.host, self.port, rel_url)