diff --git a/.isort.cfg b/.isort.cfg
index b46c472..bc7bfab 100644
--- a/.isort.cfg
+++ b/.isort.cfg
@@ -1,2 +1,2 @@
 [settings]
-known_third_party = numpy,ome_zarr,pytest,setuptools,vispy
+known_third_party = dask,numpy,ome_zarr,pytest,setuptools,vispy,zarr
diff --git a/napari_ome_zarr/_reader.py b/napari_ome_zarr/_reader.py
index f39dfa9..fb84299 100644
--- a/napari_ome_zarr/_reader.py
+++ b/napari_ome_zarr/_reader.py
@@ -10,12 +10,14 @@
 from typing import Any, Dict, Iterator, List, Optional
 
 import numpy as np
-from .ome_zarr_reader import read_ome_zarr
+
 # from ome_zarr.io import parse_url
 from ome_zarr.reader import Label, Node, Reader
 from ome_zarr.types import LayerData, PathLike, ReaderFunction
 from vispy.color import Colormap
 
+from .ome_zarr_reader import read_ome_zarr
+
 LOGGER = logging.getLogger("napari_ome_zarr.reader")
 
 METADATA_KEYS = ("name", "visible", "contrast_limits", "colormap", "metadata")
diff --git a/napari_ome_zarr/ome_zarr_reader.py b/napari_ome_zarr/ome_zarr_reader.py
index 557b30d..9bc46ef 100644
--- a/napari_ome_zarr/ome_zarr_reader.py
+++ b/napari_ome_zarr/ome_zarr_reader.py
@@ -1,28 +1,24 @@
-
-
 # zarr v3
 
-import zarr
-from zarr import Group
-import numpy as np
+from typing import Any, Callable, Dict, List, Tuple, Union
+
 import dask.array as da
-from typing import List
+import numpy as np
+import zarr
 from vispy.color import Colormap
-
-from typing import Any, Callable, Dict, List, Tuple, Union
+from zarr import Group
 
 LayerData = Union[Tuple[Any], Tuple[Any, Dict], Tuple[Any, Dict, str]]
 
 
-class Spec():
-
+class Spec:
     def __init__(self, group: Group):
         self.group = group
 
     @staticmethod
     def matches(group: Group) -> bool:
         return False
-    
+
     def data(self) -> List[da.core.Array] | None:
         return None
 
@@ -36,8 +32,7 @@ def children(self):
     def iter_nodes(self):
         yield self
         for child in self.children():
-            for ch in child.iter_nodes():
-                yield ch
+            yield from child.iter_nodes()
 
     def iter_data(self):
         for node in self.iter_nodes():
@@ -53,7 +48,6 @@ def get_attrs(group: Group):
 
 
 class Multiscales(Spec):
-
     @staticmethod
     def matches(group: Group) -> bool:
         return "multiscales" in Spec.get_attrs(group)
@@ -97,8 +91,8 @@ def metadata(self):
             rsp["colormap"] = colormaps
         return rsp
 
-class Bioformats2raw(Spec):
 
+class Bioformats2raw(Spec):
     @staticmethod
     def matches(group: Group) -> bool:
         attrs = Spec.get_attrs(group)
@@ -114,17 +108,15 @@ def children(self):
             if Multiscales.matches(g):
                 rv.append(Multiscales(g))
         return rv
-    
 
-class Plate(Spec):
 
+class Plate(Spec):
     @staticmethod
     def matches(group: Group) -> bool:
         return "plate" in Spec.get_attrs(group)
 
 
 class Label(Multiscales):
-
     @staticmethod
     def matches(group: Group) -> bool:
         # label must also be Multiscales
@@ -138,12 +130,10 @@ def metadata(self) -> Dict[str, Any] | None:
 
 
 def read_ome_zarr(url):
-
     def f(*args: Any, **kwargs: Any) -> List[LayerData]:
-
         results: List[LayerData] = list()
 
-        # TODO: handle missing file 
+        # TODO: handle missing file
         root_group = zarr.open(url)
 
         print("Root group", root_group.attrs.asdict())
@@ -170,5 +160,5 @@ def f(*args: Any, **kwargs: Any) -> List[LayerData]:
                 results.append(rv)
 
         return results
-    
+
     return f