## How to Achieve True Immutability in Python Objects: A Comparative Look at Approaches

Implementing Immutable Objects in Python

In Python, making an immutable object can present challenges. One common solution involves subclassing a tuple, as demonstrated in the provided code snippet. However, this approach introduces the drawback of accessing attributes through indices.

Pure Python Solution

An elegant solution proposed in the answer is to utilize Python's collections.namedtuple type. This type behaves similarly to the tuple subclass approach but offers additional advantages:

• Conciseness: namedtuple offers a shorter syntax for defining the immutable object.
• Compatibility: It supports serialization with pickle and copy.

To create an immutable object with namedtuple:

<code class="python">Immutable = collections.namedtuple("Immutable", ["a", "b"])</code>

Addressing Access to Indexed Attributes

While namedtuple resolves the issue of attribute modification via __setattr__, it still allows access to attributes through indices like [0] and [1]. This limitation can be mitigated by carefully structuring your code to avoid relying on these indirect methods.

Alternative Approach with C Extension

In cases where a more involved implementation is necessary, a C extension can be developed to provide true immutability by:

• Using __slots__ to allocate memory for attributes instead of using the dynamic __dict__ attribute.
• Defining custom setters and getters to strictly control attribute access.

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