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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(self, filename=None):
 """ Download snapshot to filename :param str filename: fully qualified path including filename .zip :raises EngineCommandFailed: IOError occurred downloading snapshot :return: None """

        if not filename:
            filename = '{}{}'.format(self.name, '.zip')
        
        try:
            self.make_request(
                EngineCommandFailed,
                resource='content',
                filename=filename)

        except IOError as e:
            raise EngineCommandFailed("Snapshot download failed: {}"
                                      .format(e))