Python 3 — Deep Dive Part 4 Oop High Quality

class Circle: def __init__(self, radius): self.radius = radius # Uses setter if defined @property def radius(self): return self._radius

class Foo: def __init__(self): self.__secret = 42 def get_secret(self): return self.__secret f = Foo() print(f._Foo__secret) # 42 – still accessible, but harder to accidentally access python 3 deep dive part 4 oop high quality

class Singleton: _instance = None def __new__(cls, *args, **kwargs): if cls._instance is None: cls._instance = super().__new__(cls) return cls._instance s1 = Singleton() s2 = Singleton() print(s1 is s2) # True class Circle: def __init__(self, radius): self