Respect "Connection: close" headers sent by HTTP clients. A HTTP client can indicate that it doesn't support (or doesn't want) persistent connections by sending this header. This not only makes the server more compliant with the RFC, but also reduces the run time of test-http-proxy when run with python 2.3 from ~125s to ~5s (it doesn't affect it with python 2.4, which was already ~5s).

200 Script output follows
content-type: text/plain
content-length: 157
content-disposition: filename=sometext.txt

This is just some random text
that will go inside the file and take a few lines.
It is very boring to read, but computers don't
care about things like that.
host - - [date] "GET /?f=f165dc289438;file=sometext.txt;style=raw HTTP/1.1" 200 -