diff --git a/pytorch_lightning/callbacks/model_checkpoint.py b/pytorch_lightning/callbacks/model_checkpoint.py
index eac8349004ad98..073b437b4cf89e 100644
--- a/pytorch_lightning/callbacks/model_checkpoint.py
+++ b/pytorch_lightning/callbacks/model_checkpoint.py
@@ -289,7 +289,8 @@ def __validate_init_configuration(self):
             )
         if self.every_n_train_steps > 0 and self.every_n_val_epochs > 0:
             raise MisconfigurationException(
-                f'Invalid values for every_n_train_steps={self.every_n_train_steps} and every_n_val_epochs={self.every_n_val_epochs}.'
+                f'Invalid values for every_n_train_steps={self.every_n_train_steps}'
+                ' and every_n_val_epochs={self.every_n_val_epochs}.'
                 'Both cannot be enabled at the same time.'
             )
         if self.monitor is None:
diff --git a/tests/checkpointing/test_model_checkpoint.py b/tests/checkpointing/test_model_checkpoint.py
index 73fff72a8362a2..ae7d5b772652f3 100644
--- a/tests/checkpointing/test_model_checkpoint.py
+++ b/tests/checkpointing/test_model_checkpoint.py
@@ -536,7 +536,10 @@ def test_invalid_every_n_train_steps(tmpdir):
 
 
 def test_invalid_every_n_train_steps_val_epochs_combination(tmpdir):
-    """ Make sure that a MisconfigurationException is raised if both every_n_val_epochs and every_n_train_steps are enabled together. """
+    """
+    Test that a MisconfigurationException is raised if both
+    every_n_val_epochs and every_n_train_steps are enabled together.
+    """
     with pytest.raises(MisconfigurationException, match=r'.*Both cannot be enabled at the same time'):
         ModelCheckpoint(dirpath=tmpdir, every_n_train_steps=1, every_n_val_epochs=2)
     # These should not fail