diff --git a/etrago/analyze/plot.py b/etrago/analyze/plot.py
index 9f3c7fd7..01fe2d5d 100644
--- a/etrago/analyze/plot.py
+++ b/etrago/analyze/plot.py
@@ -39,7 +39,7 @@
     import cartopy.crs as ccrs
 except ImportError:
     cartopy_present = False
-    
+
 from geoalchemy2.shape import to_shape  # noqa: F401
 from pyproj import Proj, transform
 from shapely.geometry import LineString, Point
@@ -50,7 +50,6 @@
 
 if "READTHEDOCS" not in os.environ:
 
-
     from etrago.execute import import_gen_from_links
 
 __copyright__ = (
diff --git a/etrago/cluster/electrical.py b/etrago/cluster/electrical.py
index 1194101e..6f6568f9 100755
--- a/etrago/cluster/electrical.py
+++ b/etrago/cluster/electrical.py
@@ -27,7 +27,6 @@
 logger = logging.getLogger(__name__)
 
 if "READTHEDOCS" not in os.environ:
-    
 
     from pypsa import Network
     from pypsa.clustering.spatial import (
diff --git a/etrago/disaggregate/spatial.py b/etrago/disaggregate/spatial.py
index 2ff21fe8..768a2d51 100644
--- a/etrago/disaggregate/spatial.py
+++ b/etrago/disaggregate/spatial.py
@@ -51,6 +51,7 @@
     "pieterhexen, fwitte, AmeliaNadal, cjbernal071421"
 )
 
+
 class Disaggregation:
     def __init__(self, original_network, clustered_network, busmap, skip=()):
         """
diff --git a/etrago/tools/io.py b/etrago/tools/io.py
index b648eef7..100e0790 100644
--- a/etrago/tools/io.py
+++ b/etrago/tools/io.py
@@ -58,12 +58,11 @@
 
 logger = logging.getLogger(__name__)
 
-if "READTHEDOCS" not in os.environ: 
+if "READTHEDOCS" not in os.environ:
 
     from sqlalchemy.orm.exc import NoResultFound
     import saio
 
-    
 
 carr_ormclass = "Source"