This work focuses on the development of a code to simplify the calculation of doses absorbed by the population due to radioactive releases following the steam generator tube rupture (SGTR) in the 1450 MWe French N4 nuclear reactor. This accident releases radioactive water into the environment in liquid and steam phases, and the standard approach to retrieve the dose is long and intricate. In fact, it requires three codes: the thermohydraulic code, the code related to activity calculation, and that related to atmospheric dispersion. Therefore, to accelerate the dose estimation, a consistent Python code that unifies these three models is required.