Pythonic essentials

The idioms and safety nets real Python code relies on.

Lessons

• While loops & control — A while loop repeats as long as a condition stays True — perfect when you don’t know the count in advance.
• List comprehensions — A list comprehension builds a list in one readable line — the most Pythonic idiom you’ll use daily.
• Tuples & sets — Tuples are fixed, ordered groups (great for returning several values); sets are unordered collections of unique items.
• Dictionaries in depth — Beyond storing key→value, dictionaries shine when you iterate them and look things up safely.
• Error handling — Real programs meet bad input. try/except lets your code recover instead of crashing.
• Essentials boss — Comprehensions, dicts and error handling in one gauntlet. Clear it to reach Python for data.