Why Can't I Assign Attributes to Python's 'object' Class?

Understanding the Restriction on Attribute Assignment to Simple Objects

Python employs the concept of attributes to represent properties or data associated with objects. However, there is a specific restriction when attempting to assign attributes to an instance of the basic "object" class. To understand this behavior, we delve into the fundamental design principles of Python.

The Need for a Dictionary: dict

When assigning attributes to an object, Python requires access to a dictionary within that object. This dictionary is where the assigned attributes and their values are stored. However, instances of the "object" class do not possess this dictionary by default.

Overhead and the Absence of dict

Creating and maintaining a dictionary for every object, even for those without arbitrarily assignable attributes, would introduce significant overhead. As such, Python optimizes memory usage by not equipping "object" instances with __dict__. This results in a space-saving benefit for objects that do not require attribute assignment.

Inheriting from Object and dict

When creating a class that inherits from the "object" class, Python automatically provides a dict dictionary for instances of the subclass. This inheritance allows for attribute assignment within the subclass while retaining the ability to access the inherited attributes of the "object" class. Python effectively balances the need for flexibility and optimization in this manner.

Special Mechanisms for Customized Attribute Management

Python provides alternative mechanisms to accommodate situations where a specific type of object requires only a limited number of additional attributes. One such mechanism is the slots special attribute. By defining __slots__, objects are restricted to accessing only the specified set of attributes, saving memory while still allowing some customization.

In summary, Python's restriction on assigning attributes to simple "object" instances stems from the lack of a dictionary for efficient storage. Inherited classes and special mechanisms provide options for attribute management with varying levels of flexibility and optimization.

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