[Tutor] Help with Matplotlib labels

[Sean Carolan]

> I also noticed another issue with my stacked bar graph; the total
> height of the bar is the size of the largest number of the dataset,
> and not the total of all the individual items.  Anyone matplotlib
> experts out there who can weigh in?

I figured out what was going on here; the bars were all rendering on
top of one another.  Adjustments to the "bottom" parameter have fixed
the issue.