diff --git a/spynnaker/pyNN/external_devices_models/machine_munich_motor_device.py b/spynnaker/pyNN/external_devices_models/machine_munich_motor_device.py
index ee2215c0d8..1ca373f220 100644
--- a/spynnaker/pyNN/external_devices_models/machine_munich_motor_device.py
+++ b/spynnaker/pyNN/external_devices_models/machine_munich_motor_device.py
@@ -136,8 +136,8 @@ def parse_extra_provenance_items(
                     "or decrease the number of neurons per core.")
 
     @overrides(AbstractGeneratesDataSpecification.generate_data_specification)
-    def generate_data_specification(
-            self, spec: DataSpecificationGenerator, placement: Placement):
+    def generate_data_specification(self, spec: DataSpecificationGenerator,
+                                    placement: Placement) -> None:
         # reserve regions
         self.reserve_memory_regions(spec)
 
diff --git a/spynnaker/pyNN/models/neuron/population_machine_local_only_combined_vertex.py b/spynnaker/pyNN/models/neuron/population_machine_local_only_combined_vertex.py
index 0ec684654b..5ad4e396c6 100644
--- a/spynnaker/pyNN/models/neuron/population_machine_local_only_combined_vertex.py
+++ b/spynnaker/pyNN/models/neuron/population_machine_local_only_combined_vertex.py
@@ -287,8 +287,8 @@ def get_recorded_region_ids(self) -> List[int]:
         return ids
 
     @overrides(AbstractGeneratesDataSpecification.generate_data_specification)
-    def generate_data_specification(
-            self, spec: DataSpecificationGenerator, placement: Placement):
+    def generate_data_specification(self, spec: DataSpecificationGenerator,
+                                    placement: Placement) -> None:
         rec_regions = self._pop_vertex.neuron_recorder.get_region_sizes(
             self.vertex_slice)
         rec_regions.extend(self._pop_vertex.synapse_recorder.get_region_sizes(
diff --git a/spynnaker/pyNN/models/neuron/population_machine_vertex.py b/spynnaker/pyNN/models/neuron/population_machine_vertex.py
index bc4a0539ce..da745f0d05 100644
--- a/spynnaker/pyNN/models/neuron/population_machine_vertex.py
+++ b/spynnaker/pyNN/models/neuron/population_machine_vertex.py
@@ -321,8 +321,8 @@ def get_recorded_region_ids(self) -> List[int]:
         return ids
 
     @overrides(AbstractGeneratesDataSpecification.generate_data_specification)
-    def generate_data_specification(
-            self, spec: DataSpecificationGenerator, placement: Placement):
+    def generate_data_specification(self, spec: DataSpecificationGenerator,
+                                    placement: Placement) -> None:
         rec_regions = self._pop_vertex.neuron_recorder.get_region_sizes(
             self.vertex_slice)
         rec_regions.extend(self._pop_vertex.synapse_recorder.get_region_sizes(
diff --git a/spynnaker/pyNN/models/neuron/population_neurons_machine_vertex.py b/spynnaker/pyNN/models/neuron/population_neurons_machine_vertex.py
index ed4d4ae840..5c683f33ef 100644
--- a/spynnaker/pyNN/models/neuron/population_neurons_machine_vertex.py
+++ b/spynnaker/pyNN/models/neuron/population_neurons_machine_vertex.py
@@ -257,8 +257,8 @@ def get_recorded_region_ids(self) -> List[int]:
         return ids
 
     @overrides(AbstractGeneratesDataSpecification.generate_data_specification)
-    def generate_data_specification(
-            self, spec: DataSpecificationGenerator, placement: Placement):
+    def generate_data_specification(self, spec: DataSpecificationGenerator,
+                                    placement: Placement) -> None:
         assert self.__sdram_partition is not None
         rec_regions = self._pop_vertex.neuron_recorder.get_region_sizes(
             self.vertex_slice)
diff --git a/spynnaker/pyNN/models/neuron/population_synapses_machine_vertex_lead.py b/spynnaker/pyNN/models/neuron/population_synapses_machine_vertex_lead.py
index 654ffde40e..9b8a5ef08b 100644
--- a/spynnaker/pyNN/models/neuron/population_synapses_machine_vertex_lead.py
+++ b/spynnaker/pyNN/models/neuron/population_synapses_machine_vertex_lead.py
@@ -113,8 +113,8 @@ def get_recorded_region_ids(self) -> List[int]:
         return ids
 
     @overrides(AbstractGeneratesDataSpecification.generate_data_specification)
-    def generate_data_specification(
-            self, spec: DataSpecificationGenerator, placement: Placement):
+    def generate_data_specification(self, spec: DataSpecificationGenerator,
+                                    placement: Placement) -> None:
         rec_regions = self._pop_vertex.synapse_recorder.get_region_sizes(
             self.vertex_slice)
         self._write_common_data_spec(spec, rec_regions)
diff --git a/spynnaker/pyNN/models/neuron/population_synapses_machine_vertex_shared.py b/spynnaker/pyNN/models/neuron/population_synapses_machine_vertex_shared.py
index 9a3e605673..6e878e4f1a 100644
--- a/spynnaker/pyNN/models/neuron/population_synapses_machine_vertex_shared.py
+++ b/spynnaker/pyNN/models/neuron/population_synapses_machine_vertex_shared.py
@@ -57,8 +57,8 @@ def __init__(
         self.__synapse_references = synapse_references
 
     @overrides(AbstractGeneratesDataSpecification.generate_data_specification)
-    def generate_data_specification(
-            self, spec: DataSpecificationGenerator, placement: Placement):
+    def generate_data_specification(self, spec: DataSpecificationGenerator,
+                                    placement: Placement) -> None:
         rec_regions = self._pop_vertex.synapse_recorder.get_region_sizes(
             self.vertex_slice)
         self._write_common_data_spec(spec, rec_regions)
diff --git a/spynnaker/pyNN/models/spike_source/spike_source_poisson_machine_vertex.py b/spynnaker/pyNN/models/spike_source/spike_source_poisson_machine_vertex.py
index 754f892862..e2e52523e3 100644
--- a/spynnaker/pyNN/models/spike_source/spike_source_poisson_machine_vertex.py
+++ b/spynnaker/pyNN/models/spike_source/spike_source_poisson_machine_vertex.py
@@ -354,8 +354,8 @@ def __conn(synapse_info: SynapseInformation
             'AbstractGenerateConnectorOnHost', synapse_info.connector)
 
     @overrides(AbstractGeneratesDataSpecification.generate_data_specification)
-    def generate_data_specification(
-            self, spec: DataSpecificationGenerator, placement: Placement):
+    def generate_data_specification(self, spec: DataSpecificationGenerator,
+                                    placement: Placement) -> None:
         spec.comment("\n*** Spec for SpikeSourcePoisson Instance ***\n\n")
         # if we are here, the rates have changed!
         self.__rate_changed = True
diff --git a/spynnaker/pyNN/models/utility_models/delays/delay_extension_machine_vertex.py b/spynnaker/pyNN/models/utility_models/delays/delay_extension_machine_vertex.py
index 34917a7db8..3901d99a88 100644
--- a/spynnaker/pyNN/models/utility_models/delays/delay_extension_machine_vertex.py
+++ b/spynnaker/pyNN/models/utility_models/delays/delay_extension_machine_vertex.py
@@ -267,8 +267,8 @@ def get_binary_start_type(self) -> ExecutableType:
         return ExecutableType.USES_SIMULATION_INTERFACE
 
     @overrides(AbstractGeneratesDataSpecification.generate_data_specification)
-    def generate_data_specification(
-            self, spec: DataSpecificationGenerator, placement: Placement):
+    def generate_data_specification(self, spec: DataSpecificationGenerator,
+                                    placement: Placement) -> None:
         vertex = placement.vertex
 
         # Reserve memory: