del — Advanced Examples

Deletes a variable, list item, dictionary entry, or object attribute

EasyIntermediateAdvancedExpert

del with descriptors

Customizing deletion with __delete__ and __delattr__.

python
class ProtectedAttribute:
    def __set_name__(self, owner, name):
        self.name = name
        self.private_name = f"_{name}"

    def __get__(self, obj, objtype=None):
        return getattr(obj, self.private_name, None)

    def __set__(self, obj, value):
        setattr(obj, self.private_name, value)

    def __delete__(self, obj):
        raise AttributeError(f"Cannot delete {self.name}")

class User:
    name = ProtectedAttribute()
    email = ProtectedAttribute()

    def __init__(self, name, email):
        self.name = name
        self.email = email

u = User("Alice", "alice@example.com")
print(f"Name: {u.name}")

try:
    del u.name
except AttributeError as e:
    print(f"Protected: {e}")
Expected Output
Name: Alice
Protected: Cannot delete name

Descriptors can implement __delete__ to control what happens when 'del obj.attr' is used. This enables read-only or protected attributes.

Want to try these examples interactively?

Open Advanced Playground
← Intermediate ExamplesExpert Examples →