The Lazy Unpacker

A medium Python interview practice problem on DataDriven. Write and execute real python code with instant grading.

Domain

Python

Difficulty

medium

Seniority

L4

Problem

A nightly job emits grouped metric readings as a list `nested` whose entries are either numbers or further lists, nested to arbitrary depth. Collapse it into a single flat list of every non-list value, preserving the left-to-right order in which they appear. An empty `nested`, or one holding only empty lists, comes back as an empty list.

Summary

Peel back every layer until only the values remain.

Practice This Problem

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