🧩 Memory Basics

Python programs manipulate objects. Variables don’t “contain” the object — they refer to it.

This topic focuses on:

• object identity: id()
• mutability vs immutability
• avoiding unnecessary copies using memoryview

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✅ Object Identity & References

a = [1, 2, 3]
b = a

print(id(a) == id(b))  # True (same object)

a and b are two names pointing to the same list.

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✅ Mutability

• Mutable objects can change “in place” (list, dict, set).
• Immutable objects can’t (int, float, str, tuple). “Changing” them creates a new object.

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✅ Views with memoryview

If you slice bytes, you often create a copy. With memoryview(), you can create a view into the same underlying buffer.

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🔍 Key Takeaways

• Variables hold references to objects.
• Mutability decides whether changes affect the same object.
• memoryview helps avoid copies for binary data.

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