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docs/installation.md

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+## Requirements
+
+PG-RAD requires Python `>=3.12.4` and `<3.13`. It has been tested on `3.12.9`. The guides below assume a unix-like system. You can check the Python version you have installed as follows:
+
+```
+python --version
+```
+
+If you don't have the right version installed there are various ways to get a compatible version, such as [pyenv](https://github.com/pyenv/pyenv?tab=readme-ov-file#installation).
+
+## Installation (CLI)
+
+<!--pipx seems like a possible option to install python package in a contained environment on unix-->
+
+Lorem ipsum
+
+## Installation (Python module)
+
+If you are interested in using PG-RAD in another Python project, create a virtual environment first:
+
+```
+python -m venv .venv
+```
+
+Then install PG-RAD in it:
+
+```
+source .venv/bin/activate
+(.venv) pip install git+https://github.com/pim-n/pg-rad
+```
+
+See how to get started with PG-RAD with your own Python code [here](pg-rad-in-python).
+
+## For developers
+```
+git clone https://github.com/pim-n/pg-rad
+cd pg-rad
+git checkout dev
+```
+
+or
+
+```
+git@github.com:pim-n/pg-rad.git
+cd pg-rad
+git checkout dev
+```