A little one step.

Trying Dolf's script. At first, I got an error, and Dolf told me about Python's Indent. Check and try again. Oh, I got it. A little bit, I advanced. Python script, it's a interesting. :-)

1. There are no selected face. (The script works on Object mode)

2. Run Script.

3. Into Edit mode. Some faces are selected.

This script contains some 'Selection Style', this result is applied the last one in the script.