As an example of a Python script in a workflow, two interactive tools (with very similar interface) using Python and matplotlib have been developed for the FORS instrument.
One tool allows the user to view the results of the wavelength calibration of slit spectra.
Another tool allows the user to view the results of the alignment of the above mentioned wavelength solution (based on arc lamp spectra) to a set of sky lines observed on a scientific exposure.
A document describing these tools can be downloaded here.