To try out:
- copy to pygments dir (something like /Library/Python/2.7/site-packages/Pygments-1.4-py2.7.egg/pygments/lexers)
- run 'python _mappings.py' in lexers dir
- run 'pygmentize -O style=colorful sample.fan'

While working on this I use workflow like this:
0. Symlink from lexers dir to mercurial repo
1. After modifying lexer code run something like this to see results in terminal (if terminal supports colors):
  sudo python /Library/Python/2.7/site-packages/Pygments-1.4-py2.7.egg/pygments/lexers/_mapping.py ; pygmentize  ~/work/fantom-pygments/sample.fan 
2. To get a complete html, exec command like this:
   pygmentize -f html -O full,style=colorful -o sample-colorful.html sample.fan