def multiply_filter(left, right):
    """ Automatic multiply on MO

    :param left: MO
    :param right: MO
    :returns: MO if it is a special case, nothing other wise
    """
    try:
        if left == 0:
            return left
    except TypeError:
        pass
    try:
        if right == 0:
            return right
    except TypeError:
        pass
    try:
        if left == 1:
            return right
    except TypeError:
        pass
    try:
        if right == 1:
            return left
    except TypeError:
        pass
