# Given base = [1, 2, 3] and extra = [4, 5, 6], use extend() to add all items from extra into base

Canonical URL: <https://datadriven.io/problems/given-base-1-2-3-and-extra-4-5-6-use-extend-t-44260c41>

Domain: Python · Difficulty: medium

## Problem

Given base = [1, 2, 3] and extra = [4, 5, 6], use extend() to add all items from extra into base. Print base, then print its length.

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