This gentoo overlay repository contains serveral ebuilds generated by gentoo-pypi-generator.
You can run eselect repository enable pypi-sci to enable this overlay.
Clone this repo to /var/db/repos/gentoo-pypi-sci.
Write /etc/portage/repos.conf/pypi-sci.conf as:
[pypi-sci]
location = /var/db/repos/gentoo-pypi-sci