def process_split(session, config, items):
    split = config.getoption("--split")
    if not split:
        return
    m = sp.match(split)
    if not m:
        raise ValueError("split must be a string of the form a/b "
                         "where a and b are ints.")
    i, t = map(int, m.groups())
    start, end = (i-1)*len(items)//t, i*len(items)//t

    if t < i:
        # remove elements from end of list first
        del items[end:]
    del items[:start]
dataset/ETHPy150Open sympy/sympy/sympy/conftest.py/process_split/swapped operands of `<`