How to ask for help with a program that does not work

A program that does not work is normal. Even experienced programmers spend a lot of time on it.

When you ask for help here, please include:

1. The program, in a code block, as short as you can make it.
2. What you expected to happen.
3. What happened instead. Copy the last line of the error message. It names the kind of error.
4. What you already tried.

The error name often points to the problem: a NameError means a name was never created, an IndexError means a position that does not exist, and a TypeError means that two different kinds of value were mixed. Reading the last line first saves a lot of time.