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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 _get_scale_and_shape(self,parm):
 """ Obtains appropriate model scale and shape latent variables Parameters parm : np.array Transformed latent variable vector Returns None (changes model attributes) """


        if self.scale is True:
            if self.shape is True:
                model_shape = parm[-1]  
                model_scale = parm[-2]
            else:
                model_shape = 0
                model_scale = parm[-1]
        else:
            model_scale = 0
            model_shape = 0 

        if self.skewness is True:
            model_skewness = parm[-3]
        else:
            model_skewness = 0

        return model_scale, model_shape, model_skewness