Tag Archives: Python scopes

Python Scopes – the places where variables are defined and looked up

It is essential to understand what names mean in Python. When you use a name in a program, Python creates, changes, or looks up the name in what is known as a namespace, a place where names live. The term “scope” refers to a namespace.

Names in Python begin to exist when they are first assigned values, and they must be assigned before they are used.

All names assigned inside a function are associated with that function’s namespace which means that names assigned inside a def can only be seen by the code within that def, they do not clash with variables outside the def (even if the same names are used; an a variable inside a def is different than an a variable outside the def).

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