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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 layer_height(self, layer_int):
 """ Get the layer height by layer id number. :param layer_int: :return: float, height of the soil layer """

        if layer_int == self.n_layers:
            if self.height is None:
                return None
            return self.height - self.layer_depth(layer_int)
        else:
            return self.layer_depth(layer_int + 1) - self.layer_depth(layer_int)