I am out of trial and error again Lists

[Seymore4Head]

On Fri, 24 Oct 2014 19:18:12 +0200, "Albert Visser"
<albert.visser at gmail.com> wrote:

>On Fri, 24 Oct 2014 19:03:47 +0200, Seymore4Head  
><Seymore4Head at hotmail.invalid> wrote:
>
>>
>> http://i.imgur.com/DTc5zoL.jpg
>>
>> The interpreter.   I don't know how to use that either.
>>
>
>It's what's on the left hand side of your screenshot. You can simply type  
>Python statements following the >>> prompt and hit enter to examine the  
>result, instead of pushing F5 to run your code

I guess I am confusing the Interpreter with the debugger.  Someone
suggested I use the Interpreter to step through line by line.
I don't know how to do that.