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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 useFahlmanActivationFunction(self):
 """ Change the network to use Fahlman's default activation function for all layers. Must be called after all layers have been added. """

        self.activationFunction = self.activationFunctionFahlman
        self.ACTPRIME = self.ACTPRIME_Fahlman
        self.actDeriv = self.actDerivFahlman
        for layer in self:
            layer.minTarget, layer.minActivation = -0.5, -0.5 
            layer.maxTarget, layer.maxActivation = 0.5, 0.5