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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 reconstruct(self, t:Tensor, x:Tensor=None):
        "Reconstruct one of the underlying item for its data `t`."
        return self[0].reconstruct(t,x) if has_arg(self[0].reconstruct, 'x') else self[0].reconstruct(t)