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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def bonus_damage(self):
 """ Returns a tuple of form 'bonus damage, armor type' if unit does bonus damage against armor type Light = 1; Armored = 2; Biological = 3; Mechanical = 4; Robotic = 5; Psionic = 6; Massive = 7; Structure = 8; Hover = 9; Heroic = 10; Summoned = 11 """

        # TODO Consider unit with ability attacks like Oracle, Thor, Baneling
        if self._weapons:
            for weapon in self._weapons:
                if weapon.damage_bonus:
                    b = weapon.damage_bonus[0]
                    return b.bonus, b.attribute