<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def CredibleInterval(self, percentage=90):
 """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 """

        prob = (1 - percentage / 100.0) / 2
        interval = self.Value(prob), self.Value(1 - prob)
        return interval