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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 _get_netengine_backend(self):
 """ returns the netengine backend specified in self.backend for internal use only """

        # extract backend class name, eg: AirOS or OpenWRT
        backend_class_name = self.backend.split('.')[-1]
        # convert to lowercase to get the path
        backend_path = self.backend.lower()
        # import module by its path
        module = import_module(backend_path)
        # get netengine backend class
        BackendClass = getattr(module, backend_class_name)

        return BackendClass