chore: bump flake8 to v4 and add autopep8 (#93)

* chore: bump `flake8` to v4 and add `autopep8`

Signed-off-by: Jan Kowalleck <[email protected]>

* chore: make pep8 known in the contrib docs

Signed-off-by: Jan Kowalleck <[email protected]>

Author: jkowalleck

CONTRIBUTING.md

@@ -12,6 +12,15 @@ To install dev-dependencies and tools:
 poetry install
 ```
 
+## Code style
+
+This project uses [PEP8] Style Guide for Python Code.  
+Get it applied via:
+
+```shell
+poetry run autopep8 --in-place -r .
+```
+
 ## Testing
 
 ```shell
@@ -27,4 +36,5 @@ to show that you agree to publish your changes under the current terms and licen
 git commit --signed-off ...
 ```
 
-[poetry]: https://python-poetry.org
+[poetry]: https://python-poetry.org
+[PEP8]: https://www.python.org/dev/peps/pep-0008

poetry.lock

@@ -55,13 +55,14 @@ types-setuptools = ">= 57.0.0"
 types-toml = "^0.10.0"
 
 [tool.poetry.dev-dependencies]
-pdoc3 = "^0.10.0"
 tox = "^3.24.3"
 coverage = "^6.2"
 mypy = "^0.920"
-flake8 = "^3.9.2"
-flake8-annotations = "^2.0"
+autopep8 = "^1.6.0"
+flake8 = "^4.0.1"
+flake8-annotations = {version = "^2.7.0", python = ">= 3.6.2"}
 flake8-bugbear = "^21.11.29"
+pdoc3 = "^0.10.0"
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]