Update README.md with Sarah's suggestion

Co-authored-by: SarahAlidoost <[email protected]>

README.md

@@ -2,7 +2,8 @@
 
 Integrated code of SCOPE and STEMMUS.
 
-SCOPE is a radiative transfer and energy balance model, and STEMMUS model is a two-phase mass and heat transfer model. For more information about the coupling between these two models, please check [this reference](https://gmd.copernicus.org/articles/14/1379/2021/).
+SCOPE is a radiative transfer and energy balance model, and STEMMUS model is a two-phase mass and heat transfer model. For more information about the coupling between these two models, please check [this reference](https://gmd.copernicus.org/articles/14/1379/2021/). Before running the model, you need to prepare input data and a configuration file. This can be done using the python package
+[PyStemmusScope](https://pystemmusscope.readthedocs.io).  
 
 <img width="500" alt="Logo" src=./docs/assets/imgs/coupling_scheme.png>
 (by Zeng & Su, 2021)