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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 RMSError(self):
 """ Returns Root Mean Squared Error for all output layers in this network. """

        tss = 0.0
        size = 0
        for layer in self.layers:
            if layer.type == 'Output':
                tss += layer.TSSError()
                size += layer.size
        return math.sqrt( tss / size )