Iterators

Main idea

Iterator yields one item at a time via next().

Tip

Use when streaming data.

Watch out

Trying to reuse exhausted iterator.

Read this next

Iterators is used in many real programs. Right now you are in Advanced Engineering.

Core idea:
Iterator yields one item at a time via next().

Read the example code on this page. Then write your own short version.

Tip:
Use when streaming data.

Watch out for:
Trying to reuse exhausted iterator.

Your challenge:
Create custom countdown iterator.

Use the editor in the challenge lab. When your output looks correct and there is no error, press the green button to unlock the next topic.

Example code

Copy this example if it helps. Change it so it matches Iterators.

# Topic: Iterators
def main():
    sample = "edit me"
    # TODO: apply Iterators concept here
    result = sample
    print("Result:", result)

if __name__ == "__main__":
    main()

Challenge

Create custom countdown iterator.

Before you can finish: your output should include at least 16 characters; at least 1 non-empty line(s); no crash traceback—fix errors until the program runs cleanly.

Use Run. Read the output. Change your code until the task is done.

Starter reference

# Challenge starter for Iterators
def solve():
    # Write your solution here
    pass

print("Update solve() and run")

Your code

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