def bprop(self, error, alpha=1.0, beta=0.0):
        for l in reversed(self.layers):
            b = beta if l is self.layers[-1] else 1
            l.bprop(error, alpha=alpha, beta=b)
        return self.deltas
dataset/ETHPy150Open NervanaSystems/neon/neon/layers/container.py/MergeSum.bprop/original