The Column Transformer
A easy Python mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- Python
- Difficulty
- easy
- Seniority
- L3
Interview Prompt
Given rows (list of dicts) and transforms (dict mapping a column name to a STRING of Python lambda source, e.g. 'lambda x: x.upper()'), evaluate each lambda string into a callable and apply it to that column's value in every row. Return a new list of transformed rows; columns without a transform are left unchanged and the original rows are not mutated. Preserve each row's original key order.
Summary
Each column gets its function.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write your python solution with real code execution
- Get instant feedback and a hire/no-hire decision