class Sample:
    def __init__(self, a):
        self.a = a

    def __add__(self, s):
        if isinstance(s, Sample):
            return Sample(self.a + s.s)

        if isinstance(s, int):
            return Sample(self.a + s)

    def __str__(self):
        return str(self.a)

a = 10
s = Sample(10)
result = s + a
print(result)