  Most of the solar physicists use very expensive software for data reduction
and visualization. We present hereafter a reliable freeware solution based on
the Python language. This is made possible by the association of the latter
with a small set of additional libraries developed in the scientific community.
It provides then a very powerful and economical alternative to other
interactive data languages. Although it can also be used for any kind of
post-processing of data, we demonstrate the capabities of such a set of
freeware tools using THeMIS observations of the second solar spectrum.
