diff --git a/scripts/add_electricity.py b/scripts/add_electricity.py
index 57a18a73..aa201c84 100755
--- a/scripts/add_electricity.py
+++ b/scripts/add_electricity.py
@@ -120,11 +120,13 @@ def calculate_annuity(n, r):
     else:
         return 1 / n
 
+
 def add_missing_carrier(n):
     components = [n.buses, n.generators, n.lines, n.links, n.storage_units, n.stores]
     for c in components:
-        missing_carrier = np.setdiff1d(c.carrier.unique(),n.carriers.index)
-        n.madd("Carrier",missing_carrier)
+        missing_carrier = np.setdiff1d(c.carrier.unique(), n.carriers.index)
+        n.madd("Carrier", missing_carrier)
+
 
 def _add_missing_carriers_from_costs(n, costs, carriers):
     missing_carriers = pd.Index(carriers).difference(n.carriers.index)
@@ -837,7 +839,7 @@ if __name__ == "__main__":
         estimate_renewable_capacities(n, snakemake.config)
 
     update_p_nom_max(n)
-    
+
     add_missing_carrier(n)
     add_nice_carrier_names(n, snakemake.config)
 
diff --git a/scripts/add_existing_baseyear.py b/scripts/add_existing_baseyear.py
index 1cc84a36..a8a07322 100644
--- a/scripts/add_existing_baseyear.py
+++ b/scripts/add_existing_baseyear.py
@@ -22,8 +22,8 @@ import numpy as np
 import pypsa
 import xarray as xr
 from _helpers import override_component_attrs, update_config_with_sector_opts
-from prepare_sector_network import cluster_heat_buses, define_spatial, prepare_costs
 from add_electricity import add_missing_carrier
+from prepare_sector_network import cluster_heat_buses, define_spatial, prepare_costs
 
 cc = coco.CountryConverter()
 
@@ -667,7 +667,7 @@ if __name__ == "__main__":
         cluster_heat_buses(n)
 
     n.meta = dict(snakemake.config, **dict(wildcards=dict(snakemake.wildcards)))
-    
+
     add_missing_carrier(n)
 
     n.export_to_netcdf(snakemake.output[0])
diff --git a/scripts/add_extra_components.py b/scripts/add_extra_components.py
index dcd000cd..88606305 100644
--- a/scripts/add_extra_components.py
+++ b/scripts/add_extra_components.py
@@ -57,8 +57,8 @@ import pandas as pd
 import pypsa
 from _helpers import configure_logging
 from add_electricity import (
-    add_missing_carrier,
     _add_missing_carriers_from_costs,
+    add_missing_carrier,
     add_nice_carrier_names,
     load_costs,
 )
@@ -120,8 +120,8 @@ def attach_stores(n, costs, elec_opts):
             e_cyclic=True,
             capital_cost=costs.at["hydrogen storage underground", "capital_cost"],
         )
-        
-        n.madd("Carrier",["H2 electrolysis","H2 fuel cell"])
+
+        n.madd("Carrier", ["H2 electrolysis", "H2 fuel cell"])
 
         n.madd(
             "Link",
@@ -164,8 +164,8 @@ def attach_stores(n, costs, elec_opts):
             capital_cost=costs.at["battery storage", "capital_cost"],
             marginal_cost=costs.at["battery", "marginal_cost"],
         )
-        
-        n.madd("Carrier",["battery charger","battery discharger"])
+
+        n.madd("Carrier", ["battery charger", "battery discharger"])
 
         n.madd(
             "Link",
@@ -218,8 +218,8 @@ def attach_hydrogen_pipelines(n, costs, elec_opts):
     h2_links.index = h2_links.apply(lambda c: f"H2 pipeline {c.bus0}-{c.bus1}", axis=1)
 
     # add pipelines
-    n.add("Carrier","H2 pipeline")
-    
+    n.add("Carrier", "H2 pipeline")
+
     n.madd(
         "Link",
         h2_links.index,
@@ -252,7 +252,7 @@ if __name__ == "__main__":
     attach_storageunits(n, costs, elec_config)
     attach_stores(n, costs, elec_config)
     attach_hydrogen_pipelines(n, costs, elec_config)
-    
+
     add_missing_carrier(n)
 
     add_nice_carrier_names(n, snakemake.config)
diff --git a/scripts/base_network.py b/scripts/base_network.py
index ecf21e1f..87504ce7 100644
--- a/scripts/base_network.py
+++ b/scripts/base_network.py
@@ -714,7 +714,7 @@ def base_network(
     n.name = "PyPSA-Eur"
 
     n.set_snapshots(pd.date_range(freq="h", **config["snapshots"]))
-    n.madd("Carrier",["AC","DC"])
+    n.madd("Carrier", ["AC", "DC"])
 
     n.import_components_from_dataframe(buses, "Bus")
     n.import_components_from_dataframe(lines, "Line")
diff --git a/scripts/prepare_sector_network.py b/scripts/prepare_sector_network.py
index c0def274..a0d2f472 100644
--- a/scripts/prepare_sector_network.py
+++ b/scripts/prepare_sector_network.py
@@ -22,6 +22,7 @@ from _helpers import (
     override_component_attrs,
     update_config_with_sector_opts,
 )
+from add_electricity import add_missing_carrier
 from build_energy_totals import build_co2_totals, build_eea_co2, build_eurostat_co2
 from networkx.algorithms import complement
 from networkx.algorithms.connectivity.edge_augmentation import k_edge_augmentation
@@ -29,7 +30,6 @@ from pypsa.geo import haversine_pts
 from pypsa.io import import_components_from_dataframe
 from scipy.stats import beta
 from vresutils.costdata import annuity
-from add_electricity import add_missing_carrier
 
 logger = logging.getLogger(__name__)
 
@@ -3399,7 +3399,7 @@ if __name__ == "__main__":
         cluster_heat_buses(n)
 
     n.meta = dict(snakemake.config, **dict(wildcards=dict(snakemake.wildcards)))
-    
+
     add_missing_carrier(n)
 
     n.export_to_netcdf(snakemake.output[0])