Python Data Model Explained: Identity, Equality, and Mutability Basics

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A tutorial series on DEV Community introduces Python's data model, starting with foundational concepts that confuse many developers. The first part explains that every value in Python is an object with three core properties: identity, type, and value. The article clarifies the difference between identity comparison using 'is' and equality comparison using '==', noting that singletons like None should always be checked with 'is'. It also distinguishes between mutable types, such as lists and dicts, and immutable types, such as integers and strings, explaining how mutation changes an object in place while reassignment points a name to a new object. The series targets readers already familiar with basic Python syntax and aims to prevent subtle bugs caused by aliasing and unexpected side effects.

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