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Python Itertools Chains
intermediatepython
Background
Itertools provides memory-efficient tools for working with iterators, essential for large or infinite data streams.
Problem
Write a function that takes multiple lists, chains them into a single iterable, and returns the first N unique elements.
Input
Multiple lists of elements and a count N.
Output
A list of the first N unique elements from the chained iterables.
Sample tests
Sample 1
Input: [1,2], [2,3], [3,4], N=3
Expected: [1, 2, 3]
Your solution
Learning objective
Learn itertools.chain for lazy concatenation and efficient unique element extraction.