fix and improve readme (#375)

README.md

@@ -551,61 +551,24 @@ that are already converted to the PIE format.
 
 <!-- github-only -->
 
-✨📚✨ [Read the full documentation](https://pytorch-ie.readthedocs.io/)
+<!-- TODO ✨📚✨ [Read the full documentation](https://pytorch-ie.readthedocs.io/) -->
 
 ## 🔧 Project Development
 
 ### Setup
 
-This project is build with [Poetry](https://python-poetry.org/). It is recommended, to install Poetry via
-[pipx](https://pypa.github.io/pipx/).
+This project is build with [Poetry](https://python-poetry.org/). If not yet done, follow the
+[Poetry installation guide](https://python-poetry.org/docs/#installation) to install it. Then, install all
+dependencies (including for development) for PyTorch-IE by calling the following command from the root of the
+repository:
 
-0. To install `pipx`, execute the following (taken from
-   [pipx installation instructions](https://pypa.github.io/pipx/installation/)):
-
-    ```bash
-    # [IF PIP IS NOT AVAILABLE] install pip
-    python -m ensurepip --upgrade
-    # [OPTIONAL] update pip
-    python -m pip install --upgrade pip
-
-    # install pipx (requires pip 19.0 or later)
-    python3 -m pip install --user pipx
-    python3 -m pipx ensurepath
-    ```
-
-    NOTE: This installs `pipx` globally!
-
-1. Install Poetry via `pipx` (or see [Poetry installation guide](https://python-poetry.org/docs/#installation)):
-
-    ```bash
-    pipx install poetry
-    ```
-
-    NOTE: This installs `pipx` globally!
-
-2. [IF REQUIRED PYTHON VERSION IS NOT AVAILABLE] install required python:
-
-    ```bash
-    # for instance, to install python3.9 on Ubuntu:
-    sudo add-apt-repository ppa:deadsnakes/ppa
-    sudo apt update
-    sudo install python3.9
-
-    # or via conda:
-    conda create -n python3.9=python3.9 -y
-    conda activate python3.9
-    ```
-
-3. Finally, install the dependencies (including for development) for PyTorch-IE:
-
-    ```bash
-    poetry install --with dev
-    ```
+```bash
+poetry install --with dev
+```
 
-    NOTE: If the installation gets stuck, try if disabling experimental parallel installer helps
-    ([source](https://github.com/python-poetry/poetry/issues/3352#issuecomment-732761629)):
-    `poetry config experimental.new-installer false`
+NOTE: If the installation gets stuck, try if disabling experimental parallel installer helps
+([source](https://github.com/python-poetry/poetry/issues/3352#issuecomment-732761629)):
+`poetry config experimental.new-installer false`
 
 ### Testing and code quality checks
 
@@ -638,12 +601,14 @@ To run all commands that also run on GitHub CI, call:
 poetry run nox
 ```
 
-To run more tests (also tests marked with `@pytest.mark.slow`, but without tests for all datasets which would take forever), call:
+You can also start a shell with Poetry's virtual environment activated by calling:
 
 ```bash
-poetry run nox -s tests_no_local_datasets-3.9
+poetry shell
 ```
 
+This allows you to run above commands without the `poetry run` prefix.
+
 ### Updating Dependencies
 
 Call this to update individual packages:
@@ -671,7 +636,7 @@ Since this project is based on the [Cookiecutter template](https://cookiecutter-
    `git push origin release`
 5. Create a PR for that `release` branch on GitHub.
 6. Wait until checks passed successfully.
-7. Integrate the PR into the main branch (use `rebase` to have a linear history). This triggers the GitHub Action that
+7. Integrate the PR into the main branch. This triggers the GitHub Action that
    creates all relevant release artefacts and also uploads them to PyPI.
 8. Cleanup: Delete the `release` branch.