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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 files(self):
 """Extract files to download from GitHub payload."""

        tag_name = self.release['tag_name']
        repo_name = self.repository['full_name']

        zipball_url = self.release['zipball_url']
        filename = u'{name}-{tag}.zip'.format(name=repo_name, tag=tag_name)

        response = self.gh.api.session.head(zipball_url)
        assert response.status_code == 302, \
            u'Could not retrieve archive from GitHub: {0}'.format(zipball_url)

        yield filename, zipball_url