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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 addUrl(self, url):
 """Add url to binder """


        if url not in self.urls:
            self.urls.append(url)

        root = self.etree
        t_urls = root.find('urls')

        if not t_urls:
            t_urls = ctree.SubElement(root, 'urls')

        t_url = ctree.SubElement(t_urls, 'url')
        t_url.text = url

        return True