Add pre-commit hooks

.pre-commit-config.yaml

@@ -0,0 +1,17 @@
+# https://pre-commit.com
+
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.0.1
+    hooks:
+      - id: end-of-file-fixer
+      - id: trailing-whitespace
+      - id: check-yaml
+      - id: debug-statements
+      - id: mixed-line-ending
+# black as python formatter
+  - repo: https://github.com/psf/black
+    rev: 22.3.0
+    hooks:
+      - id: black
+        files: python/

README.md

@@ -2,6 +2,7 @@
 
 [![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.3739617.svg)](https://doi.org/10.5281/zenodo.3739617)
 
+[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
 ## Overview and resources
 
 The Community Terrestrial Systems Model.