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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 _propagate(self, x, influences, **kwargs):
 """Propagate a single batch of examples through the network."""

        activation, difference_x = self.forward(x)
        update = self.backward(difference_x, influences, activation)
        # If batch size is 1 we can leave out the call to mean.
        if update.shape[0] == 1:
            self.weights += update[0]
        else:
            self.weights += update.mean(0)

        return activation