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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 download_url(self, url, **kwargs):
 """ Download a URL to the workspace. Args: url (string):
 URL to download to directory **kwargs : See :py:mod:`ocrd.resolver.Resolver` Returns: The local filename of the downloaded file """

        if self.baseurl and '://' not in url:
            url = join(self.baseurl, url)
        return self.resolver.download_to_directory(self.directory, url, **kwargs)