diff --git a/aiida_hyperqueue/scheduler.py b/aiida_hyperqueue/scheduler.py
index 1f65a65..a762e4b 100644
--- a/aiida_hyperqueue/scheduler.py
+++ b/aiida_hyperqueue/scheduler.py
@@ -26,9 +26,9 @@
     "FINISHED": JobState.DONE,
 }
 
+
 class AiiDAHypereQueueDeprecationWarning(Warning):
-    """Class for HypereQueue plugin deprecations.
-    """
+    """Class for HypereQueue plugin deprecations."""
 
 
 class HyperQueueJobResource(JobResource):
@@ -72,10 +72,10 @@ def validate_resources(cls, **kwargs):
                     "Must specify `num_cpus`, or (`num_machines` and `num_mpiprocs_per_machine`)"
                 )
             else:
-                message = 'The `num_machines` and `num_mpiprocs_per_machine` for setting hyperqueue resources are deprecated. '
-                'Please set `num_cpus` and `memory_mb`.'
+                message = "The `num_machines` and `num_mpiprocs_per_machine` for setting hyperqueue resources are deprecated. "
+                "Please set `num_cpus` and `memory_mb`."
 
-                message = f'{message} (this will be removed in aiida-hyperqueue v1.0)'
+                message = f"{message} (this will be removed in aiida-hyperqueue v1.0)"
                 warnings.warn(message, AiiDAHypereQueueDeprecationWarning, stacklevel=3)
         else:
             if not isinstance(resources.num_cpus, int):