Python delattr() Function

The delattr() function in Python is used to delete an attribute from an object. It’s useful when you want to dynamically remove properties from user-defined objects.

Syntax

delattr(object, name)

Parameters:

• object – The object whose attribute you want to delete
• name – A string representing the name of the attribute

Returns:

• Nothing. It deletes the attribute in place.

Example 1: Deleting an Attribute from an Object

class Person:
    name = "Alice"
    age = 25

# Delete the 'age' attribute
delattr(Person, 'age')

# Now let's try to access it
p = Person()
print(hasattr(p, 'age'))

False

Example 2: With Object Instances

class Car:
    def __init__(self):
        self.color = "red"
        self.brand = "Toyota"

c = Car()
delattr(c, 'color')

print(hasattr(c, 'color'))

False

Use Case: When is delattr() Useful?

• When you want to remove an attribute dynamically at runtime
• Used in metaprogramming and frameworks that modify object structure
• Cleaning up unnecessary attributes before serialization

Equivalent Code Using del

You can also delete attributes like this:

del object.attribute

But delattr() lets you use the attribute name as a string, which is helpful for dynamic situations.

Common Errors

• AttributeError: If the attribute doesn't exist
• TypeError: If the attribute name is not a string

Interview Tip

delattr() is handy in scenarios involving reflection, metaclasses, and frameworks like Django where models are modified dynamically.

Summary

• delattr(object, "attr") removes the named attribute
• Works like del obj.attr but uses a string name
• Raises AttributeError if the attribute doesn’t exist

Practice Problem

Create a class Student with attributes name and grade. Delete the grade attribute using delattr() and print whether the attribute still exists.

class Student:
    def __init__(self):
        self.name = "Bob"
        self.grade = "A"

s = Student()
delattr(s, 'grade')
print(hasattr(s, 'grade'))

Expected Output:

False