Navigating Namespaces and Scope in Python

Johan Vergeer 11 Lessons 27m basics python

In a program of any complexity, you’ll create hundreds or thousands of names, each pointing to a specific object. How does Python keep track of all these names so that they don’t interfere with one another? This course covers Python namespaces, the structures used to organize the symbolic names assigned to objects in a Python program.

In this course, you’ll learn:

How Python organizes symbolic names and objects in namespaces
When Python creates a new namespace
How namespaces are implemented
How variable scope determines symbolic name visibility
What is the LEGB rule

What’s Included:

11 Lessons
Video Subtitles and Full Transcripts
2 Downloadable Resources
Accompanying Text-Based Tutorial
Q&A With Python Experts: Ask a Question
Certificate of Completion

Downloadable Resources:

Related Learning Paths:

Introduction to Python

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Navigating Namespaces and Scope in Python

11 Lessons 27m

1. Navigating Namespaces and Scope in Python (Overview) 01:07

2. Built-in Namespace 01:33

3. Global Namespace 03:17

4. Enclosing and Local Namespaces 04:18

5. Variable Scope 01:03

6. The LEGB Rule 04:00

7. Modifying Variables Out of Scope 03:08

8. The global Declaration 03:28

9. The nonlocal Declaration 02:17

10. Scope Best Practices 02:32

11. Navigating Namespaces and Scope in Python (Summary) 00:48

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About Johan Vergeer

Hallo, my name is Johan, and I am a software engineer working for the Pythoneers at Ordina in the Netherlands. I have a soft spot for awesome software design, clean code and sharing knowledge.

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Each tutorial at Real Python is created by a team of developers so that it meets our high quality standards. The team members who worked on this tutorial are:

Christopher

Sadie

Tappan

John

Joanna

Aldren

Bryan

Jacob

Participant Comments

Dirk on March 22, 2021

Short and sweet. I liked it a lot.

Alain Rouleau on March 3, 2021

Great explanation of namespaces and the concept of scope, thanks!

I’ve seen many people try to explain these Python concepts over the years. But this is one of the best tutorials that I’ve seen. Kudos! I like how you used simple functions to explain things, introduced the globals() function, and nonlocal for enclosed functions as well. Not many people know about those.

Plus, use of the equal sign in f-strings was a nice touch. Definitely going to use that in the future. Not to mention, the "i" command line option. Pretty sure 99% of people don’t know about that feature either which allows you to start an interactive session and import a module ALL in one step. Very handy.

Keep up the good work!

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