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Home/Questions/Python/Coding/Convert the list [1, [2, 3], 4, 5, 6, [7, 8, 9]] to a single list [1, 2, 3, 4, 5, 6, 7, 8, 9].

Convert the list [1, [2, 3], 4, 5, 6, [7, 8, 9]] to a single list [1, 2, 3, 4, 5, 6, 7, 8, 9].

Python/Codingeasy0.2 min readPremium
Frequency
Low
Asked at 1 company
Category
179
questions in Python/Coding
Difficulty Split
127E|24M|28H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Cognizant
Expert AnswerPremium
38 wordsInterview-ready
**Flatten recursive:** `def flatten(lst): return sum([flatten(x) if isinstance(x,list) else [x] for x in lst], [])`. Or `result=[]; [result.extend(flatten(x) if isinstance(x,list) else [x]) for x in lst]`. **One-liner:** `sum` with empty start....
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