Level 4Exercise #84

Flatten an iterable of iterables

Flatten an iterator of batches without unpacking all batches as arguments.

What you’ll practice

This Level 4 exercise focuses on chain.from_iterable in the Itertools curriculum. Solve the challenge prompt above using clear, idiomatic Python and the relevant language or standard-library tools.

Relevant Python reference: itertools.chain.

Sample Test Cases

Example #1

Input:flatten_batches(iter([[1,2],[3]]))

Output:[1,2,3]

Reference Solution

Reveal Reference Solution

def flatten_batches(batches) -> list:
    from itertools import chain
    return list(chain.from_iterable(batches))

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Flatten an iterable of iterables

What you’ll practice

Sample Test Cases

Further Reading

Reference Solution