diff --git a/examples/tutorials/data/hawc.py b/examples/tutorials/data/hawc.py
index 83227db737..73a72f3993 100644
--- a/examples/tutorials/data/hawc.py
+++ b/examples/tutorials/data/hawc.py
@@ -60,7 +60,7 @@
 ######################################################################
 # Chose which estimator we will use
 
-which = "NN"
+energy_estimator = "NN"
 
 
 ######################################################################
@@ -85,8 +85,8 @@
 # Load the tables
 
 data_path = "$GAMMAPY_DATA/hawc/crab_events_pass4/"
-hdu_filename = "hdu-index-table-" + which + "-Crab.fits.gz"
-obs_filename = "obs-index-table-" + which + "-Crab.fits.gz"
+hdu_filename = f"hdu-index-table-{energy_estimator}-Crab.fits.gz"
+obs_filename = f"obs-index-table-{energy_estimator}-Crab.fits.gz"
 
 # there is only one observation table
 obs_table = ObservationTable.read(data_path + obs_filename)
diff --git a/gammapy/datasets/map.py b/gammapy/datasets/map.py
index e613506afc..e2ac9e0348 100644
--- a/gammapy/datasets/map.py
+++ b/gammapy/datasets/map.py
@@ -51,7 +51,7 @@ def create_map_dataset_geoms(
     migra_axis=None,
     rad_axis=None,
     binsz_irf=None,
-    reco_psf=False
+    reco_psf=False,
 ):
     """Create map geometries for a `MapDataset`
 
@@ -89,7 +89,7 @@ def create_map_dataset_geoms(
     geom_irf = geom_image.to_binsz(binsz=binsz_irf)
 
     if reco_psf:
-        geom_psf = geom_irf.to_cube([rad_axis,geom.axes["energy"]])
+        geom_psf = geom_irf.to_cube([rad_axis, geom.axes["energy"]])
     else:
         geom_psf = geom_irf.to_cube([rad_axis, energy_axis_true])
 
@@ -653,7 +653,7 @@ def create(
             rad_axis=rad_axis,
             migra_axis=migra_axis,
             binsz_irf=binsz_irf,
-            reco_psf=reco_psf
+            reco_psf=reco_psf,
         )
 
         kwargs.update(geoms)
diff --git a/gammapy/datasets/tests/test_map.py b/gammapy/datasets/tests/test_map.py
index 38f4aa8208..f25db23775 100644
--- a/gammapy/datasets/tests/test_map.py
+++ b/gammapy/datasets/tests/test_map.py
@@ -18,7 +18,7 @@
     EnergyDependentMultiGaussPSF,
     EnergyDispersion2D,
     PSFMap,
-    RecoPSFMap
+    RecoPSFMap,
 )
 from gammapy.makers.utils import make_map_exposure_true_energy, make_psf_map
 from gammapy.maps import HpxGeom, Map, MapAxis, RegionGeom, WcsGeom, WcsNDMap
@@ -1875,6 +1875,7 @@ def test_peek(images):
     with mpl_plot_check():
         dataset.peek()
 
+
 def test_create_psf_reco(geom):
     dat = MapDataset.create(geom, reco_psf=True)
-    assert isinstance(dat.psf, RecoPSFMap)
\ No newline at end of file
+    assert isinstance(dat.psf, RecoPSFMap)