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Today's code · Sunday

Crew list

Press Run to see the output here.

Replace "You" with your name, then add one more seat. Open the full editor →

Newest articles

Discover the latest in space science and Python programming. Our newest articles blend astronomy concepts with coding challenges to fuel your cosmic curiosity.

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A robot standing next to a Japanese restaurant, the cover image for an article on whether learning Python is still worth it in the age of AI

Is It Worth Learning Python in the Age of AI? (2026)

AI now writes a large share of new code, so is learning Python still worth your time? Yes, but for a different reason than ten years ago. Using job data, developer surveys and recent studies on learning with AI, we look at what changed and where Python’s

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Beginner’s guide to Python functions: code example with def, parameters and return

Python Functions for Beginners

Learn to write your own Python functions, from your first def to return values, default parameters and scope, with runnable examples, common mistakes and six practice projects.

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Converting decimal numbers to Rocky's base-6 Eridian number system in Python

Base 6 Number System in Python

In Project Hail Mary, the alien engineer Rocky counts in base 6 because he has two hands with three fingers each. In this article, you'll build Python programs that convert between decimal, base-6, and Eridian notation.

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New in the community forum

Questions and answers from other people learning Python.

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Quiz of the week

A different quiz every Monday. How many will you get right?

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Python Type Conversion and input() Quiz

Free beginner quiz on Python type conversion and input(): 15 questions on int(), float(), str(), bool() and reading numbers from the user.

  • Questions: 15
  • Easy
  • Free account needed

Today's challenges

Three challenges, different every day. Fix or write the code and let the tests check it.

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Backup that isn't

backup = crew gives one list two names, so removing someone from the backup removes them from the live roster too. Predict it, prove it with is, fix it with copy(), then plan a crew swap on a real copy.

  • Fix the code
  • Medium
  • 3 stages

Check every reading

Extend the OK/WARN/CRITICAL check from Alert level so a for loop runs it over every temperature in a list, then count the WARN and CRITICAL readings for a summary line.

  • Write the code
  • Easy
  • 2 stages

Numbered checklist

Print a pre-flight checklist numbered from 1 with enumerate(list, start=1), then tick off the items the crew has already done with [x] and leave the rest as [ ].

  • Write the code
  • Easy
  • 2 stages

Today's examples

Three short programs to read, run and change. A new set tomorrow.

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Creating Sets

Sets store only unique elements without a specific order.

  • Audio
  • set
  • unique

Set Operations

Adding and removing elements from a set. Basic set operations.

  • Audio
  • set
  • add
  • remove

Mathematical Set Operations

Union, intersection and difference of sets. Mathematical operations from set theory.

  • Audio
  • set
  • union
  • intersection

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