[jonnycomputer]

    len(list(filter(lambda line: all([abs(x) >= 1 and abs(x) <= 3 for x in line]) and (all([x > 0 for x in line]) or all([x < 0 for x in line])), diffs)))

Well, point taken about the ordering, but there are many more legible ways to have written that code. Not everything has to be a one liner.

even:

    def f(diffs):
        cond = lambda line: all([1 <= abs(x) <= 3 for x in line]) and (
            all([x > 0 for x in line]) or all([x < 0 for x in line])
        )
        items = filter(cond, diffs)
        return len(list(items))