Python test2 2015b / ul. 4

class Mnozina:
    def __init__(self):
        self.pole = []

    def __repr__(self):
        #print(list(sorted(self.pole)))
        return (str(sorted(self.pole)))

    def add(self, cislo):
        #if cislo in self:
        if cislo not in self:
            self.pole.append(cislo)

    def discard(self, cislo):
        if cislo in self:
            self.pole.pop(cislo)

    def __contains__(self, cislo):
        #return self.pole.index(cislo) >= 0
        return cislo in self.pole

    def __len__(self):
        return len(self.pole)

    def zjednotenie(self, ina):
        # for i in ina.pole:
        for i in ina:
            #self.append(i)
            self.pole.append(i)


b = Mnozina()

b.add(5)
b.add(10)
b.add(6)

a = [4, 7, 6]

b.zjednotenie(a)