name = {
    124: "A",
    444: "B",
    952: "C"}
user_id = 375
print(name.get(user_id, "D"))

class A:
    def __init__(self):
        print('A', end='')
        super().__init__()
class B(A):
    def __init__(self):
        print('B', end='')
        super().__init__()
class C(A):
    def __init__(self):
        print('C', end='')
        super().__init__()
class D(B, C):
    def __init__(self):
        print('D', end='')
        super().__init__()

X = D()

class X:
    def __init__(self):
        print('X', end='')
class Y:
    def __init__(self):
        print('Y', end='')
class Z(X, Y):
    def __init__(self):
        print('Z', end='')
        super().__init__()

z = Z()

class A:
    def __init__(self):
        self.x = 1

a = A()
b = a
b.x = 5
print(a.x)

class A:
    def hello(self):
        return "Hello from A"

class B(A):
    def hello(self):
        return "Hello from B"

b = B()
print(b.hello())

class A:
    @staticmethod
    def stat():
        return "Static"

    @classmethod
    def cls(cls):
        return cls.__name__

    def inst(self):
        return self.__class__.__name__

a = A()

print(A.stat(), A.cls(), a.inst())

class A:
    def __init__(self, value):
        self._x = value

    @property
    def x(self):
        return self._x * 2

a = A(5)
print(a.x)

class A:
    def __str__(self):
        return "Custom str"

a = A()
print(a)

class A:
    def __init__(self, val):
        self.val = val

    def __eq__(self, other):
        return self.val == other.val

a1 = A(3)
a2 = A(3)
print(a1 == a2)