User-agent: *           # directed to all spiders
Disallow: /_
Disallow: /images
Disallow: /fpdb
Disallow: /w3c
Disallow: /download

User-agent: Slurp
Crawl-delay: 99

User-agent: Python-urllib
Disallow: /

User-agent: Theophrastus 
Disallow: /