The call_GRAM.py script can be used to query the atmospheric density of Mars as a function of altitude, latitude, and time.
These density are extrapolated based on the data from Mars GRAM 2010, by NASA. This extrapolation is made using a 3d-interpolation of an atmosphere lookup table.
The variable file_path at the beginning of the Python file refers to the path of the tpdmsy11.txt data file that is distributed with Mars GRAM 2010.
It can be requested to NASA by filling the form specified at this page.