zipstream.py is a zip archive generator based on python 3.3's
zipfile.py. It was created to generate a zip file generator for
streaming (ie web apps). This is beneficial for when you want to
provide a downloadable archive of a large collection of regular files,
which would be infeasible to generate the archive prior to downloading
or of a very large file that you do not want to store entirely on disk
or on memory.

The archive is generated as an iterator of strings, which, when
joined, form the zip archive.