diff --git a/python/podio/frame_iterator.py b/python/podio/frame_iterator.py
index 6976ffb43..ec47a43e7 100644
--- a/python/podio/frame_iterator.py
+++ b/python/podio/frame_iterator.py
@@ -3,8 +3,8 @@
 
 # pylint: disable-next=import-error # gbl is a dynamic module from cppyy
 from cppyy.gbl import std
-from podio.frame import Frame
 import cppyy
+from podio.frame import Frame
 
 
 class FrameCategoryIterator:
@@ -32,8 +32,8 @@ def __next__(self):
       frame_data = self._reader.readNextFrame(self._category)
     except AttributeError:
       frame_data = self._reader.readNextEntry(self._category)
-    except std.runtime_error:
-      raise StopIteration
+    except std.runtime_error as error:
+      raise StopIteration from error
     if frame_data:
       return Frame(std.move(frame_data))
 
@@ -67,9 +67,9 @@ def __getitem__(self, entry):
             'points to the library folder of the installation of podio and also to the library '
             'folder with your data model\n')
       raise
-    except std.runtime_error:
+    except std.runtime_error as error:
       raise IndexError('Unable to read frame, you might be trying to read beyond bounds or a '
-                       'non-existent category')
+                       'non-existent category') from error
 
     if frame_data:
       if isinstance(frame_data, cppyy.gbl.podio.ROOTFrameData):
diff --git a/python/podio/root_io.py b/python/podio/root_io.py
index e62347dd6..8bfca0f87 100644
--- a/python/podio/root_io.py
+++ b/python/podio/root_io.py
@@ -3,7 +3,7 @@
 
 from ROOT import gSystem, gInterpreter
 gSystem.Load('libpodioRootIO')  # noqa: E402
-gInterpreter.LoadFile("podio/Reader.h") # noqa: E402
+gInterpreter.LoadFile("podio/Reader.h")  # noqa: E402
 from ROOT import podio  # noqa: E402 # pylint: disable=wrong-import-position
 
 from podio.base_reader import BaseReaderMixin  # pylint: disable=wrong-import-position
@@ -26,6 +26,7 @@ def __init__(self, filenames):
 
     super().__init__()
 
+
 class ROOTFrameReader(BaseReaderMixin):
   """Reader class for reading podio root files."""
 
@@ -96,6 +97,7 @@ def __init__(self, filename):
     self._writer = podio.makeWriter(filename)
     super().__init__()
 
+
 class ROOTFrameWriter(BaseWriterMixin):
   """Writer class for writing podio root files"""
   def __init__(self, filename):
diff --git a/src/RNTupleWriter.cc b/src/RNTupleWriter.cc
index dc95e9d15..79360f1e9 100644
--- a/src/RNTupleWriter.cc
+++ b/src/RNTupleWriter.cc
@@ -63,7 +63,7 @@ void RNTupleWriter::writeFrame(const podio::Frame& frame, const std::string& cat
 }
 
 void RNTupleWriter::writeFrame(const podio::Frame& frame, const std::string& category,
-                                  const std::vector<std::string>& collsToWrite) {
+                               const std::vector<std::string>& collsToWrite) {
   auto& catInfo = getCategoryInfo(category);
 
   // Use the writer as proxy to check whether this category has been initialized