class MyInt:
    def __init__(self, value):
        self.value = value
        self.posflag = False
    def __pos__(self):
        if self.posflag:
            self.posflag = not self.posflag
            self.value += 1
            return self.value
        else:
            self.posflag = not self.posflag
            return self

a = MyInt(10)
print(++a) # 11