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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 _call_backend(self, method, default, *args, **kwargs):
 """Call the backend method with args. If there is currently no backend, return default."""

        meth = getattr(self.backend, method, None)
        if meth is None:
            return default
        else:
            return meth(*args, **kwargs)