def decorator(cls):
    class Proxy:
        def __init__ (self, *args): 
            self.wrapped = cls(*args)
        def __getattr__(self, name): 
            return 1 if name == 'x' else getattr(self.wrapped, name)
    return Proxy

@decorator
class S:
    def __init__(self, x):
        self.x = x
    def square(self): 
        return self.x ** 2 
s = S(10) 
print(s.square() + s.x)

def counter(func):
    def oncall(*args): 
        oncall.calls += 1
        return func(*args) + oncall.calls
    oncall.calls = 0
    return oncall
class C:
    @counter
    def square(self, a): 
        return a ** 2
x = C()
print(x.square(2) + x.square(2))

5 >> 1 << 1

class A: pass
class B:
    def __init__(self):
        x = super()
        print(x is A, x is B)

b = B()

def f(*, name):
    print(len(name), end=" ")

try:
    f(name="vasya")
    f("sergey")
except:
    f(name="oleg")

sum(divmod(16,5), 5)

def f(x, y):
    return x ** y
print(f.__call__(3, 2) + f(2, 3))

"{0:b}{1:#o}".format(3, 8)

d = {"id": 1, "person": {"name": "Vasya", "age": 18}}
d1 = d.copy()
d1["person"]["age"] += 1
d2 = d
d2["person"]["age"] += 1
print(d["person"]["age"])