The Payload Flattener
A medium Python mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- Python
- Difficulty
- medium
- Seniority
- L3
Interview Prompt
Given a nested dict (keys map to primitive values OR to inner dicts), return a flat dict whose keys are the joined key paths using the given separator. Non-dict values become leaves with the full joined key path.
Summary
Turn a deeply nested API response into a flat row.
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