For [1, 2, 3, 4], the intended result is [4, 8]. For an empty list, it is []. Odd values are omitted, not doubled.
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Challenge
Write double_even_numbers(numbers). Return a new list containing each even number multiplied by two. Four tests must pass.
Your result will appear here.
A WORKED TASK
Solve a small challenge and learn from the tests
Implement double_even_numbers(numbers): return a new list containing only the even input numbers, doubled. Read the example comprehension, then rewrite it using an ordinary loop as practice. Run the tests after each change instead of guessing from one example.
A passing set of beginner tests covers the included cases, not every possible program property. It does not award an accredited qualification or execute against a remote judge.
What to check
- Return the list rather than only printing it.
- Keep the required function name so the tests can call your solution.
- Try zero, negative even numbers and repeated values. Do not mutate the input unless the task explicitly allows it.
TESTED & REVIEWED
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- Processing
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- The browser runtime is intentionally isolated and may not include every desktop package, system command or network feature. Verify production programs in their target Python environment.
EXAMPLE INPUT
Start small, then use your own data
Your solution
def double_even_numbers(numbers):
# Return a new list containing doubled even numbers only.
return [number * 2 for number in numbers if number % 2 == 0]For [1, 2, 3, 4], the intended result is [4, 8]. For an empty list, it is []. Odd values are omitted, not doubled.
COMMON QUESTIONS
Python Exercise Runner FAQ
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The browser downloads and starts the Python WebAssembly runtime. Later runs in the same tab are normally much faster.
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