def CredibleInterval(self, percentage=<NUM_LIT>):
cdf = self.MakeCdf()<EOL>return cdf.CredibleInterval(percentage)<EOL>
Computes the central credible interval.

        If percentage=90, computes the 90% CI.

        Args:
            percentage: float between 0 and 100

        Returns:
            sequence of two floats, low and high