No 'assert' command in last selftest

So, subj. Code in interpreter:

    type(my_army.units[0]) == Lancer
    type(my_army.units[1]) == Healer
    type(my_army.units[-1]) == Warlord

    type(enemy_army.units[0]) == Vampire
    type(enemy_army.units[-1]) == Warlord
    type(enemy_army.units[-2]) == Knight

    # 6, not 8, because only 1 Warlord per army could be
    len(enemy_army.units) == 6

    battle = Battle()

    battle.fight(my_army, enemy_army) == True

It's confusing. Fix, pls.