grokking generators and iterators

[Bob Horvath]

We have a document repository at work whose "database" is a flat text 
file. The search engine on it is lame, and I want to create a better 
one, but I need to work with the format that exists.  Having recently 
learned about generators, I thought it might be a good fit, 
Unfortunately, I am struggling to find an easy way to do it.  I am 
wondering if I just don't grok the new features, or if they aren't a 
good fix.

I don't think it matters what the format is. It is a repeating pattern 
of 5 lines.

How would you suggest writing a generator that spits out 5 line chunks 
of a file at a time?

How would you do it without generators?