diff --git a/src/uproot/models/RNTuple.py b/src/uproot/models/RNTuple.py
index 49524e981..d2523e450 100644
--- a/src/uproot/models/RNTuple.py
+++ b/src/uproot/models/RNTuple.py
@@ -340,7 +340,9 @@ def read_col_page(self, ncol, cluster_i):
         for page_desc in pagelist:
             n_elements = page_desc.num_elements
             tracker_end = tracker + n_elements
-            self.read_pagedesc(res[tracker:tracker_end], page_desc, n_elements, dtype_str, dtype)
+            self.read_pagedesc(
+                res[tracker:tracker_end], page_desc, n_elements, dtype_str, dtype
+            )
             tracker = tracker_end
 
         if dtype_byte <= uproot.const.rntuple_col_type_to_num_dict["index32"]:
@@ -392,7 +394,9 @@ def arrays(
         cluster_offset = cluster_starts[start_cluster_idx]
         entry_start -= cluster_offset
         entry_stop -= cluster_offset
-        return ak._v2.from_buffers(form, cluster_num_entries, container_dict)[entry_start:entry_stop]
+        return ak._v2.from_buffers(form, cluster_num_entries, container_dict)[
+            entry_start:entry_stop
+        ]
 
 
 # Supporting function and classes
@@ -412,6 +416,7 @@ def _recursive_find(form, res):
         if issubclass(type(form.content), ak._v2.forms.Form):
             _recursive_find(form.content, res)
 
+
 # https://github.com/jblomer/root/blob/ntuple-binary-format-v1/tree/ntuple/v7/doc/specifications.md#page-list-envelope
 class PageDescription:
     def read(self, chunk, cursor, context):