How to create an HTTP POST body - uwsgi protocol

[LiteWait]

Using a package https://github.com/andreif/uwsgi-tools/blob/master/uwsgi_tools/curl.py which works great for Unix sockets and GET requests. Problem is POST requests seem to arrive without a body. uwsgi protocol docs don't describe this very well. It appears the code in that package just appends the body (as bytes) to the header part of the request.

Is this correct, what am I missing?