object()

object()

object() is the base class from which all other classes inherit in Python. Every class in Python implicitly inherits from object unless it specifies a different base class. This makes object the root of Python’s class hierarchy.

Syntax

object()

Parameters

object() takes no parameters. It creates a new instance of the base object class.

Examples

Basic usage

# Create a basic object instance
obj = object()

print(obj)        # <object object at 0x7f7f9c5e8b80>
print(type(obj)) # <class 'object'>

Checking inheritance

Every class implicitly inherits from object:

class MyClass:
    pass

print(isinstance(MyClass(), object)) # True
print(issubclass(MyClass, object))  # True
print(issubclass(object, object))   # True

Default methods from object

All Python objects have these methods inherited from object:

obj = object()

# __repr__ - official string representation
print(repr(obj)) # <object object at 0x7f7f9c5e8b80>

# __str__ - informal string representation
print(str(obj))  # <object object at 0x7f7f9c5e8b80>

# __hash__ - hash value for use in sets/dicts
print(hash(obj)) # 8767552312507

# __eq__ - equality comparison
print(obj == object()) # False (different identity)

# __ne__ - inequality comparison
print(obj != object()) # True

Customizing with inheritance

When you define a class, it inherits all object methods, which you can override:

class Person:
    def __init__(self, name):
        self.name = name
    
    def __repr__(self):
        return f"Person({self.name!r})"
    
    def __str__(self):
        return self.name

p = Person("Alice")
print(repr(p)) # Person('Alice')
print(str(p))  # Alice

Common Patterns

Checking if something is a basic object

def is_plain_object(x):
    """Check if x is the base object class or instance."""
    return type(x) is object or x is object

print(is_plain_object(object()))     # True
print(is_plain_object(object))       # True
print(is_plain_object("hello"))      # False

Using object as a placeholder

# Sentinel value when you need a unique marker
NO_VALUE = object()

def get_value(key, default=NO_VALUE):
    # Implementation using sentinel
    pass

Errors

object() itself raises no errors, but attempting to call certain methods on instances that don’t implement them can cause issues:

# Trying to call non-existent attributes raises AttributeError
obj = object()
obj.custom_attribute  # AttributeError: 'object' has no attribute 'custom_attribute'

See Also

• type()
• isinstance()
• getattr()