Which way does it lean?

You will write your own mean and median, without the statistics module, and then a function that gives a rough word for the shape of a data set from the two averages.

The idea. The mean is the total divided by the count. The median is the middle of the sorted list, or the mean of the two middle values. Here is a rough guide. Call a data set skewed right when the mean is above the median by more than a twentieth of the range. Call it skewed left when the mean is below the median by more than that. Otherwise call it roughly symmetric.

Your tasks.

1. Finish mean_of(data).
2. Finish median_of(data). Sort a copy first.
3. Finish lean(data). Return "skewed right", "skewed left" or "roughly symmetric" by the rule above.