def pdf(self, mu):
        """
        PDF for Skew t prior

        Parameters
        ----------
        mu : float
            Latent variable for which the prior is being formed over

        Returns
        ----------
        - p(mu)
        """
        if self.transform is not None:
            mu = self.transform(mu)    
        return self.pdf_internal(mu, df=self.df0, loc=self.loc0, scale=self.scale0, gamma=self.gamma0)