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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 delete_assets(self, service_id, url=None, all=False):
 """Delete CDN assets Arguments: service_id: The ID of the service to delete from. url: The URL at which to delete assets all: When True, delete all assets associated with the service_id. You cannot specifiy both url and all. """

        self._services_manager.delete_assets(service_id, url, all)