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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 export(self, filename='element.zip'):
 """ Export this element. Usage:: engine = Engine('myfirewall') extask = engine.export(filename='fooexport.zip') while not extask.done():
 extask.wait(3) print("Finished download task: %s" % extask.message()) print("File downloaded to: %s" % extask.filename) :param str filename: filename to store exported element :raises TaskRunFailed: invalid permissions, invalid directory, or this element is a system element and cannot be exported. :return: DownloadTask .. note:: It is not possible to export system elements """

        from smc.administration.tasks import Task
        return Task.download(self, 'export', filename)