def bspe(a, b):
    """
    Sum series for exp(1)-1 between a, b, returning the result
    as an exact fraction (p, q).
    """
    if b-a == 1:
        return MPZ_ONE, MPZ(b)
    m = (a+b)//2
    p1, q1 = bspe(a, m)
    p2, q2 = bspe(m, b)
    return p1*q2+p2, q1*q2
dataset/ETHPy150Open fredrik-johansson/mpmath/mpmath/libmp/libelefun.py/bspe/original