diff --git a/gpm/gv/routines.py b/gpm/gv/routines.py
index d330552..d3f4b64 100644
--- a/gpm/gv/routines.py
+++ b/gpm/gv/routines.py
@@ -518,7 +518,8 @@ def plot_quicklook(
     "zFactorFinalNearSurface",
     "precipRateNearSurface",
 ]
-    
+
+
 def retrieve_ds_sr(start_time, end_time, extent_gr, download_sr=False):
     # Define GPM settings
     product_type = "RS"
@@ -744,15 +745,12 @@ def volume_matching(
         # Define start_time and end_time for searching SR data
         start_time = gr_min_time - np.timedelta64(10, "m")
         end_time = gr_max_time + np.timedelta64(10, "m")
-        
-        ds_sr = retrieve_ds_sr(start_time=start_time, 
-                               end_time=end_time, 
-                               extent_gr=extent_gr,
-                               download_sr=download_sr)
+
+        ds_sr = retrieve_ds_sr(start_time=start_time, end_time=end_time, extent_gr=extent_gr, download_sr=download_sr)
     else:
         try:
             ds_sr = ds_sr.gpm.crop(extent=extent_gr)
-        except Exception: 
+        except Exception:
             # GR extent is not withing SR swath
             return None
 
@@ -1247,10 +1245,10 @@ def volume_matching(
     gdf_match = gdf_match[~gdf_match["GR_counts"].isna()]
     gdf_match = gdf_match[~gdf_match["GR_Z_mean"].isna()]
 
-    # Return None if nothing left 
+    # Return None if nothing left
     if len(gdf_match) == 0:
         return None
-    
+
     # Compute ratio SR/GR volume
     gdf_match["VolumeRatio"] = gdf_match["SR_gate_volume_sum"] / gdf_match["GR_gate_volume_sum"]
 
diff --git a/gpm/gv/xradar/methods.py b/gpm/gv/xradar/methods.py
index 9d097fc..1b44efa 100644
--- a/gpm/gv/xradar/methods.py
+++ b/gpm/gv/xradar/methods.py
@@ -9,8 +9,8 @@
     get_projection_corners_from_centroids,
     get_quadmesh_from_corners,
 )
-from gpm.utils.remapping import reproject_coords
 from gpm.utils.geospatial import merge_extents
+from gpm.utils.remapping import reproject_coords
 
 
 def resolution_at_range(xr_obj, azimuth_beamwidth, elevation_beamwidth):
@@ -212,7 +212,7 @@ def get_datatree_extent(dt, max_distance=None, crs=None):
         get_extent(dt[sweep].to_dataset(), max_distance=max_distance, crs=crs) for sweep in get_datatree_sweeps(dt)
     ]
     return merge_extents(list_extent)
-  
+
 
 def get_maximum_horizontal_distance(xr_obj):
     """Return the horizontal distance from the last gate."""