Difference between the append() and extend() methods of a list.
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Python conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
The methods append() and extend() work on lists. While append() adds an element to the end of the list, extend adds another list to the end of a list.
Let's take two lists.
>>> list1,list2=[1,2,3],[5,6,7,8]
This is how append() works:
>>> list1.append(4)
>>> list1
[1, 2, 3, 4]
And this is how extend() works:
>>> list1.extend(list2)
>>> list1
[1, 2, 3, 4, 5, 6, 7, 8]
Candidate Response Strategy & Interview Tips
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- Discuss complexity & edge cases: Proactively explain time/space complexity or boundary conditions (null values, scale limits).
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