diff --git a/.github/workflows/test-charmed-katib.yaml b/.github/workflows/test-charmed-katib.yaml
index 7312c559d9e..2f95bfe9af4 100644
--- a/.github/workflows/test-charmed-katib.yaml
+++ b/.github/workflows/test-charmed-katib.yaml
@@ -18,7 +18,7 @@ jobs:
           set -eux
           sudo apt update
           sudo apt install python3-setuptools
-          sudo pip3 install black==20.8b1 flake8
+          sudo pip3 install black flake8
 
       - name: Check black
         run: black --check operators
diff --git a/operators/katib-controller/src/charm.py b/operators/katib-controller/src/charm.py
index 961b9cef778..615ac6d8e8e 100755
--- a/operators/katib-controller/src/charm.py
+++ b/operators/katib-controller/src/charm.py
@@ -15,7 +15,7 @@
 
 
 class CheckFailed(Exception):
-    """ Raise this exception if one of the checks in main fails. """
+    """Raise this exception if one of the checks in main fails."""
 
     def __init__(self, msg, status_type=None):
         super().__init__()
diff --git a/operators/katib-db-manager/src/charm.py b/operators/katib-db-manager/src/charm.py
index 5576c8ee0f4..107baf75b3b 100755
--- a/operators/katib-db-manager/src/charm.py
+++ b/operators/katib-db-manager/src/charm.py
@@ -11,7 +11,7 @@
 
 
 class CheckFailed(Exception):
-    """ Raise this exception if one of the checks in main fails. """
+    """Raise this exception if one of the checks in main fails."""
 
     def __init__(self, msg, status_type=None):
         super().__init__()
diff --git a/operators/katib-ui/src/charm.py b/operators/katib-ui/src/charm.py
index ff31a437489..aeda1c68cb2 100755
--- a/operators/katib-ui/src/charm.py
+++ b/operators/katib-ui/src/charm.py
@@ -16,7 +16,7 @@
 
 
 class CheckFailed(Exception):
-    """ Raise this exception if one of the checks in main fails. """
+    """Raise this exception if one of the checks in main fails."""
 
     def __init__(self, msg, status_type=None):
         super().__init__()