To install Rapydscript simply use easy_install or pip:
pip install rapydscript
Rapydscript requires PyMeta, written by Waldemar Kornewald, which currently does not have a PyPI package. It is included as part of the Rapydscript install.
The project is GPLv3, but the output is license free. See http://www.gnu.org/licenses/gpl-faq.html#WhatCaseIsOutputGPL.