diff --git a/openfl/component/aggregator/aggregator.py b/openfl/component/aggregator/aggregator.py
index bd57ca48af..bfea92e2ed 100644
--- a/openfl/component/aggregator/aggregator.py
+++ b/openfl/component/aggregator/aggregator.py
@@ -614,9 +614,10 @@ def send_local_task_results(self, collaborator_name, round_number, task_name,
                 collab_name for collab_name in self.authorized_cols
                 if collab_name not in self.collaborators_done
             ]
-            if len(self.stragglers) != 0: self.logger.warning(
-                f"Identified straggler collaborators: {self.stragglers}"
-            )
+            if len(self.stragglers) != 0:
+                self.logger.warning(
+                    f"Identified straggler collaborators: {self.stragglers}"
+                )
             self._end_of_round_check()
 
     def _process_named_tensor(self, named_tensor, collaborator_name):
diff --git a/openfl/component/straggler_handling_functions/cutoff_time_based_straggler_handling.py b/openfl/component/straggler_handling_functions/cutoff_time_based_straggler_handling.py
index e503ce574b..2305825750 100644
--- a/openfl/component/straggler_handling_functions/cutoff_time_based_straggler_handling.py
+++ b/openfl/component/straggler_handling_functions/cutoff_time_based_straggler_handling.py
@@ -121,8 +121,8 @@ def __straggler_time_expired(self) -> bool:
         Determines if straggler_cutoff_time is elapsed.
         """
         return (
-            self.round_start_time is not None and
-            ((time.time() - self.round_start_time) > self.straggler_cutoff_time)
+            self.round_start_time is not None
+            and ((time.time() - self.round_start_time) > self.straggler_cutoff_time)
         )
 
     def __minimum_collaborators_reported(self, num_collaborators_done) -> bool:
diff --git a/openfl/component/straggler_handling_functions/percentage_based_straggler_handling.py b/openfl/component/straggler_handling_functions/percentage_based_straggler_handling.py
index 6096a1eb48..1a8804c290 100644
--- a/openfl/component/straggler_handling_functions/percentage_based_straggler_handling.py
+++ b/openfl/component/straggler_handling_functions/percentage_based_straggler_handling.py
@@ -3,7 +3,6 @@
 
 """Percentage based Straggler Handling function."""
 from logging import getLogger
-from typing import Callable
 from openfl.component.straggler_handling_functions import StragglerHandlingPolicy
 
 
diff --git a/openfl/component/straggler_handling_functions/straggler_handling_function.py b/openfl/component/straggler_handling_functions/straggler_handling_function.py
index 31443862bd..52104b6376 100644
--- a/openfl/component/straggler_handling_functions/straggler_handling_function.py
+++ b/openfl/component/straggler_handling_functions/straggler_handling_function.py
@@ -51,7 +51,7 @@ def straggler_cutoff_check(
                 Number of collaborators finished.
             num_all_collaborators: int
                 Total number of collaborators.
-            
+
         Returns:
             bool
         """
diff --git a/openfl/native/fastestimator.py b/openfl/native/fastestimator.py
index e2d659563a..5700f61613 100644
--- a/openfl/native/fastestimator.py
+++ b/openfl/native/fastestimator.py
@@ -75,9 +75,7 @@ def fit(self):
 
         aggregator = plan.get_aggregator()
 
-        model_states = {
-            collaborator: None for collaborator in plan.authorized_cols
-        }
+        model_states = dict.fromkeys(plan.authorized_cols, None)
         runners = {}
         save_dir = {}
         data_path = 1
diff --git a/openfl/utilities/optimizers/numpy/adam_optimizer.py b/openfl/utilities/optimizers/numpy/adam_optimizer.py
index 8660a59855..79adb76bbb 100644
--- a/openfl/utilities/optimizers/numpy/adam_optimizer.py
+++ b/openfl/utilities/optimizers/numpy/adam_optimizer.py
@@ -72,7 +72,7 @@ def __init__(
         self.beta_1, self.beta_2 = betas
         self.initial_accumulator_value = initial_accumulator_value
         self.epsilon = epsilon
-        self.current_step: Dict[str, int] = {param_name: 0 for param_name in self.params}
+        self.current_step: Dict[str, int] = dict.fromkeys(self.params, 0)
 
         self.grads_first_moment, self.grads_second_moment = {}, {}