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.
