class SpaceAge(object):
    def __init__(self):
        pass

class SpaceAge(object):
    def __init__(self, seconds):
        self.seconds = seconds

    @property
    def years(self):
        return self.seconds/31557600

    def on_earth(self):
        return round(self.years, 2)

    def on_mercury(self):
        return round(self.years/0.2408467, 2)

    def on_venus(self):
        return round(self.years/0.6151976, 2)

    def on_mars(self):
        return round(self.years/1.8808158, 2)

    def on_jupiter(self):
        return round(self.years/11.862615, 2)

    def on_saturn(self):
        return round(self.years/29.447498, 2)

    def on_uranus(self):
        return round(self.years/84.016846, 2)

    def on_neptune(self):
        return round(self.years/164.79132, 2)

Add initial solution