diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 831945c0..10240279 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -17,7 +17,7 @@ repos:
         # Don't commit to master branch.
     -   id: no-commit-to-branch
 -   repo: https://github.com/psf/black
-    rev: '22.12.0'
+    rev: '23.1.0'
     hooks:
     -   id: black
         # Force black to run on whole repo, using settings from pyproject.toml
diff --git a/esmf_regrid/tests/unit/esmf_regridder/test_Regridder.py b/esmf_regrid/tests/unit/esmf_regridder/test_Regridder.py
index ef9c26ed..8f16753b 100644
--- a/esmf_regrid/tests/unit/esmf_regridder/test_Regridder.py
+++ b/esmf_regrid/tests/unit/esmf_regridder/test_Regridder.py
@@ -161,6 +161,7 @@ def test_Regridder_init_small():
     With predictable weights it is easier to check that the weights are
     associated with the correct indices.
     """
+
     # The following ASCII visualisation describes the source and target grids
     # and the indices which ESMF assigns to their cells.
     # Analysis of the weights dict returned by ESMF confirms that this is