Adding write-video flag info

Author: IshaanDesai

elastic-tube-1d/README.md

@@ -88,7 +88,7 @@ cd solid-python
 ./run.sh
 ```
 
-**Optional:** A run-time plot visualization can be trigged by passing the `--enable-plot` execution command in `run.sh` of `FluidSolver.py`.
+**Optional:** A run-time plot visualization can be trigged by passing `--enable-plot` in `run.sh` of `FluidSolver.py`. Additionally a video of the run-time plot visualization can be generated by additionally passing `--write-video`. 
 
 {% include warning.html content= "The C++ and Python solvers lead to different results. Please consider the Python results as the correct ones and refer to this [open issue](https://github.com/precice/tutorials/issues/195) for more insight. Contributions are particularly welcome here." %}