Element Counting in isply

import islpy as isl

a = isl.BasicSet("[n] -> {[i,j]: 0<= i < n and 0<= j < n and j<= i}")
print a


def count(bset):
    result = None

    for i in range(bset.dim(isl.dim_type.set)):
        dmax = bset.dim_max(i)
        dmin = bset.dim_min(i)

        length = isl.PwQPolynomial.from_pw_aff(dmax - dmin + 1)

        print "min %s" % bset.get_dim_name(isl.dim_type.set, i), dmin
        print "max %s" % bset.get_dim_name(isl.dim_type.set, i), dmax

        if result is None:
            result = length
        else:
            result = result.mul(length)

    return result

print count(a)