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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 urls(self):
 """ Provide URLconf details for the ``Api``. And all registered ``Resources`` beneath it. :return list: URL's patterns """

        urls = []

        for url_name in sorted(self.resources.keys()):

            resource = self.resources[url_name]
            urls.append(resource.as_url(
                api=self,
                name_prefix='-'.join(
                    (self.prefix, self.str_version)).strip('-'),
                url_prefix=self.str_version
            ))

        return patterns(self.prefix, *urls)