diff --git a/scripts/add_existing_baseyear.py b/scripts/add_existing_baseyear.py
index 942b1398..212ae8af 100644
--- a/scripts/add_existing_baseyear.py
+++ b/scripts/add_existing_baseyear.py
@@ -22,11 +22,10 @@ from _helpers import (
     update_config_from_wildcards,
 )
 from add_electricity import sanitize_carriers
-from prepare_sector_network import cluster_heat_buses, define_spatial, prepare_costs
-
 from definitions.heat_sector import HeatSector
 from definitions.heat_system import HeatSystem
 from definitions.heat_system_type import HeatSystemType
+from prepare_sector_network import cluster_heat_buses, define_spatial, prepare_costs
 
 logger = logging.getLogger(__name__)
 cc = coco.CountryConverter()
diff --git a/scripts/prepare_sector_network.py b/scripts/prepare_sector_network.py
index 7c6f7c61..191294b6 100644
--- a/scripts/prepare_sector_network.py
+++ b/scripts/prepare_sector_network.py
@@ -30,6 +30,9 @@ from build_energy_totals import (
     build_eurostat_co2,
 )
 from build_transport_demand import transport_degree_factor
+from definitions.heat_sector import HeatSector
+from definitions.heat_system import HeatSystem
+from definitions.heat_system_type import HeatSystemType
 from networkx.algorithms import complement
 from networkx.algorithms.connectivity.edge_augmentation import k_edge_augmentation
 from prepare_network import maybe_adjust_costs_and_potentials
@@ -37,10 +40,6 @@ from pypsa.geo import haversine_pts
 from pypsa.io import import_components_from_dataframe
 from scipy.stats import beta
 
-from definitions.heat_sector import HeatSector
-from definitions.heat_system import HeatSystem
-from definitions.heat_system_type import HeatSystemType
-
 spatial = SimpleNamespace()
 logger = logging.getLogger(__name__)