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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 update_configs(self, release):
 """ Update the fedora-atomic.git repositories for a given release """

        git_repo = release['git_repo']
        git_cache = release['git_cache']
        if not os.path.isdir(git_cache):
            self.call(['git', 'clone', '--mirror', git_repo, git_cache])
        else:
            self.call(['git', 'fetch', '--all', '--prune'], cwd=git_cache)
        git_dir = release['git_dir'] = os.path.join(release['tmp_dir'],
                                                    os.path.basename(git_repo))
        self.call(['git', 'clone', '-b', release['git_branch'],
                   git_cache, git_dir])

        if release['delete_repo_files']:
            for repo_file in glob.glob(os.path.join(git_dir, '*.repo')):
                self.log.info('Deleting %s' % repo_file)
                os.unlink(repo_file)