updated python version for doc

docs/setup.md

@@ -2,7 +2,7 @@
 
 ## Prerequisites
 
-- Python3 with a preference for [conda](https://conda.io), and python version `3.8` (higher versions *might* work, but they are **untested**).
+- Python3 with a preference for [conda](https://conda.io), and python version `3.9` (higher versions *might* work, but they are **untested**).
 - Knowledge of [managing Python environments](https://docs.python.org/3/tutorial/venv.html). The instructions below assume knowledge of the [conda management system](https://docs.conda.io/projects/conda/en/latest/user-guide/tasks/manage-environments.html).
 
 Alternatively, you can run GaNDLF via [Docker](https://www.docker.com/). This needs different prerequisites. See the [Docker Installation](#docker-installation) section below for more information. 
@@ -25,7 +25,7 @@ Alternatively, you can run GaNDLF via [Docker](https://www.docker.com/). This ne
 GaNDLF's primary computational foundation is built on PyTorch, and as such it supports all hardware types that PyTorch supports. Please install PyTorch for your hardware type before installing GaNDLF. See the [PyTorch installation instructions](https://pytorch.org/get-started/previous-versions/#v1131) for more details. An example installation using CUDA, ROCm, and CPU-only is shown below:
 
 ```bash
-(base) $> conda create -n venv_gandlf python=3.8 -y
+(base) $> conda create -n venv_gandlf python=3.9 -y
 (base) $> conda activate venv_gandlf
 (venv_gandlf) $> ### subsequent commands go here
 ### PyTorch installation - https://pytorch.org/get-started/previous-versions/#v1131