Imagine a royal decree that said: "Every building must describe_itself() ." The would say: "I am a cozy cottage." The Mansion would say: "I am a sprawling estate."
class IntegerField: def __set_name__(self, owner, name): # Python 3.6+ helper to automatically capture the attribute name self.protected_name = f"_name" def __get__(self, instance, owner): if instance is None: return self return getattr(instance, self.protected_name, 0) def __set__(self, instance, value): if not isinstance(value, int): raise TypeError(f"Value must be an integer, got type(value)") setattr(instance, self.protected_name, value) class UserProfile: age = IntegerField() user = UserProfile() user.age = 30 # Works perfectly # user.age = "thirty" # Raises TypeError Use code with caution. 3. Demystifying Multiple Inheritance and the MRO python 3 deep dive part 4 oop
class OrderedMeta(type): @classmethod def __prepare__(mcs, name, bases): return dict() # In Python 3.6+, dict preserves insertion order Imagine a royal decree that said: "Every building
def __get__(self, instance, owner): if instance is None: return self return getattr(instance, self.storage_name) Properties let you wrap attribute access behind function
Python avoids traditional explicit getter and setter methods ( get_value() / set_value() ) in favor of properties. Properties let you wrap attribute access behind function logic while maintaining clean dot-notation syntax. The Underlying Descriptor Protocol
Class decorators can often achieve similar results with less complexity. As a rule of thumb: .