L1 Improvements

[Mcrich23]

Hi Ben, My name is Morris and I am one of your students this quarter. I look forward to learning things tidbits about python that I was not aware of and discussing with you. Anyway, here is my actual PR:

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Improvement 1: Copy code from Challenge 1 to Challenge 2

Challenge 2 in Lecture 1 is all about modifying Challenge 1's program. Instead of asking students to copy and paste it below if they would like, including it already saves time and allows students to compare their program with the original.

Improvement 2: Add print statement to Debugging Slide

When demonstrating a runtime error due to assert, changing it to be correct outputs nothing. Adding a comment is a helpful visual aid for some.