diff --git a/scripts/build_energy_totals.py b/scripts/build_energy_totals.py
index fe4b9e70..24ba86bb 100644
--- a/scripts/build_energy_totals.py
+++ b/scripts/build_energy_totals.py
@@ -1066,7 +1066,9 @@ def build_eurostat_co2(eurostat: pd.DataFrame, year: int = 1990) -> pd.Series:
 
     # emissions in tCO2_equiv per MWh_th
     specific_emissions["Solid fossil fuels"] = 0.36  # Approximates coal
-    specific_emissions["Oil and petroleum products"] = 0.285  # Average of distillate and residue
+    specific_emissions["Oil and petroleum products"] = (
+        0.285  # Average of distillate and residue
+    )
     specific_emissions["Natural gas"] = 0.2  # For natural gas
 
     return eurostat_year.multiply(specific_emissions).sum(axis=1)
@@ -1099,7 +1101,9 @@ def build_co2_totals(
 
     co2 = eea_co2.reindex(countries)
 
-    for ct in pd.Index(countries).intersection(["BA", "RS", "AL", "ME", "MK", "UA", "MD"]):
+    for ct in pd.Index(countries).intersection(
+        ["BA", "RS", "AL", "ME", "MK", "UA", "MD"]
+    ):
         mappings = {
             "electricity": (ct, "+", "Electricity & heat generation", np.nan),
             "residential non-elec": (ct, "+", "+", "Residential"),