No Jenkins updates via e-mail

It seems like I have to make a pull request to the wrong location for Jenkins Homework task to respond via E-mail from my git push request.
This one suffers from the same warning as the other. Using 0 to be a lower bound on a Minimum is a dangerous move. The same goes for maximum in this case since the transactions could be either positive or negative. None is a safer choice.

    TOTAL = 0
    MAXIMUM = None
    MINIMUM = None
    for DAY in data.TRANSACTIONS:
        DTOTAL = 0
        for TRANSACTION in DAY:
            DTOTAL += TRANSACTION

        TOTAL += DTOTAL

        if DTOTAL > MAXIMUM or MAXIMUM is None:
            MAXIMUM = DTOTAL

        if DTOTAL < MINIMUM or MINIMUM is None:
            MINIMUM = DTOTAL