Exercise : Log analyzer
Given a log file, find the most frequent error messages.
Approach: Use Counter, regex to extract error message, return most_common().
Exercise : Health checker
Write a script that checks if a list of URLs are responding. Output status for each.
Approach: Use requests library, handle timeouts, print pass/fail.
Exercise : Config diff
Compare two JSON config files and output the differences.
Approach: Load both as dicts, recursively compare, output added/removed/changed keys.
Interview tip: Practice without an IDE. Many interviews use simple editors or shared docs.