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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_sync(self, remote_path, local_path, callback=None):
 """Downloads remote resources from WebDAV server synchronously. :param remote_path: the path to remote resource on WebDAV server. Can be file and directory. :param local_path: the path to save resource locally. :param callback: the callback which will be invoked when downloading is complete. """

        self.download(local_path=local_path, remote_path=remote_path)
        if callback:
            callback()