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Unit 4 Lab: Carefully Adding a Bit More Logic

--- ## Lesson Objectives - Apply what you’ve learned in Unit 4 to create a working Python program. - Wrap up Unit 4. - Q&A and transition. --- ## You Do: Unit 4 Lab — Troubleshooting Do you remember the last unit lab? You added structure to your movie app using dictionaries and classes. In today's lab, you will add error-checking, string formatting, and a `while` loop (but not an infinite one!), slightly restructuring the code as you go. **Open the [`unit-lab-4-directions`](unit-lab-4-directions.md) file to see the lab and its instructions. Follow the instructions there.** - *If your solution to the last lab didn't quite work, there's working code provided in the [`starter-code`](starter-code/movie_app.py) folder. Copy that to your local folder and work from there.* Try your best! Raise your hand if you really need help. --- ## Debrief: Unit 4 Lab — Troubleshooting How did it go? Let's go over it. Make sure you understand and that your code works — the Unit 5 lab builds off this one! --- ## Unit 4 Wrap-Up What did we cover? * Variable scope: Using the global keyword to access global variables. * The order of scope precedence that Python follows when resolving variable names. * Creating floats and flooring division. * Formatting strings. * Troubleshooting common types of errors. * Implement basic `try/except` mitigation. * Adding `print` statements to help debugging. Questions?

5 minutes **Teaching Tips:** - Briefly review the high-level learning objectives for Unit 4. - As you read each bullet aloud, ask students to give you a "fist to five." See **Talking Points** below. - Observe student votes for each item and make a mental note to follow up with individuals who are not feeling confident, or find time to reteach topics with which the majority of the class is uncomfortable. - Take time to go over questions (but remember the parking lot). **Talking Points:** - Wow, we've covered a lot! Let's take a minute to review what we've learned so far. - I'm going to read through the topics for Unit 4. As I do so, I want you to tell me how confident you feel that you've mastered each one, on a scale of 0 to 5. * Hold up your fist to indicate 0 — you don't feel confident at all that you mastered this objective. * Hold up all five fingers to indicate 5 — you feel super confident. You're an expert!