How to use the ciw.dists.distributions.CombinedDistribution function in Ciw

def __add__(self, dist):
        """
        Add two distributions such that sampling is the sum of the samples.
        """
        return CombinedDistribution(self, dist, add)

def __truediv__(self, dist):
        """
        Divide two distributions such that sampling is the ratio of the samples.
        """
        return CombinedDistribution(self, dist, truediv)

def __sub__(self, dist):
        """
        Subtract two distributions such that sampling is the difference of the samples.
        """
        return CombinedDistribution(self, dist, sub)

def __mul__(self, dist):
        """
        Multiply two distributions such that sampling is the product of the samples.
        """
        return CombinedDistribution(self, dist, mul)