$ pip install 'sphinx<1.6' blurb
$ make htmlhelp
mkdir -p build
Building NEWS from Misc/NEWS.d with blurb
PATH=./venv/bin:$PATH sphinx-build -b htmlhelp -d build/doctrees -D latex_elements.papersize=  . build/htmlhelp 
Running Sphinx v1.5.6

Extension error:
Could not import extension pyspecific (exception: cannot import name 'status_iterator' from 'sphinx.util' (/home/mdk/.venvs/tmp/lib/python3.7/site-packages/sphinx/util/__init__.py))
make: *** [Makefile:45: build] Error 1