class Akvarium():

    def __init__(self):
        self.vatten = "salt"
        self.fiskar = 14
        self.belysning = True
        self.temperatur = 22.5

    def skriv(self):
        dictionary = self.__dict__
        for a in dictionary.keys():
            print(a, dictionary[a])

box = Akvarium()
box.skriv()