diff --git a/Calorimeter/CaloRec/python/CaloRecoConfig.py b/Calorimeter/CaloRec/python/CaloRecoConfig.py
index 2776fb87aa85d554baf9b5feee117665ceef20c6..36365c7e2a51dd05b33bddee5c5818a6e9099f13 100644
--- a/Calorimeter/CaloRec/python/CaloRecoConfig.py
+++ b/Calorimeter/CaloRec/python/CaloRecoConfig.py
@@ -13,7 +13,7 @@ def CaloRecoCfg(configFlags):
 
 
         from ByteStreamCnvSvc.ByteStreamConfig import ByteStreamReadCfg
-        result.merge( ByteStreamReadCfg(configFlags,typeNames=['TileDigitsContainer/TileDigitsCnt','TileRawChannelContainer/TileRawChannelCnt']))
+        result.merge( ByteStreamReadCfg(configFlags,type_names=['TileDigitsContainer/TileDigitsCnt','TileRawChannelContainer/TileRawChannelCnt']))
 
 
         from LArROD.LArRawChannelBuilderAlgConfig import LArRawChannelBuilderAlgCfg
diff --git a/Event/ByteStreamCnvSvc/python/ByteStreamConfig.py b/Event/ByteStreamCnvSvc/python/ByteStreamConfig.py
index de44b7f9143ca2463b142b824a866d020410ec03..ccda176c396dd1d53440b7aca4ff2646e361edf6 100644
--- a/Event/ByteStreamCnvSvc/python/ByteStreamConfig.py
+++ b/Event/ByteStreamCnvSvc/python/ByteStreamConfig.py
@@ -1,71 +1,76 @@
-#
-#  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
-#
-
+#!/usr/bin/env python
+# Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
+"""module docstring
+"""
 from AthenaConfiguration.ComponentAccumulator import ComponentAccumulator
 from AthenaConfiguration.ComponentFactory import CompFactory
+from AthenaConfiguration.AllConfigFlags import ConfigFlags
+from AthenaConfiguration.TestDefaults import defaultTestFiles
+from AthenaCommon.Configurable import Configurable
+from AthenaServices.MetaDataSvcConfig import MetaDataSvcCfg
 
 
-def ByteStreamReadCfg( inputFlags, typeNames=[] ):
-    """
-    Creates accumulator for BS reading
+def ByteStreamReadCfg(flags, type_names=None):
+    """Creates resultumulator for BS reading
     """
-
-    acc = ComponentAccumulator()
-    
-    ByteStreamCnvSvc, ByteStreamEventStorageInputSvc, EventSelectorByteStream=CompFactory.getComps("ByteStreamCnvSvc","ByteStreamEventStorageInputSvc","EventSelectorByteStream",)
-
-    if inputFlags.Input.SecondaryFiles:
-        filenames = inputFlags.Input.SecondaryFiles
-        eventSelector = EventSelectorByteStream("SecondaryEventSelector", IsSecondary=True)
-        eventSelector.Input = filenames
-        acc.addService( eventSelector )
+    result = ComponentAccumulator()
+    bytestream_conversion = CompFactory.ByteStreamCnvSvc()
+    result.addService(bytestream_conversion)
+
+    bytestream_input = CompFactory.ByteStreamEventStorageInputSvc(
+        name="ByteStreamInputSvc",
+        EventInfoKey="{}EventInfo".format(
+            flags.Overlay.BkgPrefix if flags.Overlay.DataOverlay else ""
+        ),
+    )
+    result.addService(bytestream_input)
+
+    if flags.Input.SecondaryFiles:
+        event_selector = CompFactory.EventSelectorByteStream(
+            name="SecondaryEventSelector",
+            IsSecondary=True,
+            Input=flags.Input.SecondaryFiles,
+            ByteStreamInputSvc=bytestream_input.name,
+        )
+        result.addService(event_selector)
     else:
-        filenames = inputFlags.Input.Files
-        xAODMaker__EventInfoSelectorTool = CompFactory.xAODMaker.EventInfoSelectorTool
-        xconv = xAODMaker__EventInfoSelectorTool()
-        eventSelector = EventSelectorByteStream("EventSelector")
-        eventSelector.Input = filenames
-        eventSelector.HelperTools += [xconv]
-        eventSelector.SkipEvents=inputFlags.Exec.SkipEvents
-        acc.addService( eventSelector )
-        acc.setAppProperty( "EvtSel", eventSelector.name )
-
-    bsInputSvc = ByteStreamEventStorageInputSvc( "ByteStreamInputSvc" )
-    if inputFlags.Overlay.DataOverlay:
-        bsInputSvc.EventInfoKey = inputFlags.Overlay.BkgPrefix + "EventInfo"
-    acc.addService( bsInputSvc )
-
-    EvtPersistencySvc=CompFactory.EvtPersistencySvc
-    eventPersistencySvc = EvtPersistencySvc( "EventPersistencySvc" )
-    acc.addService( eventPersistencySvc )
-    
-    bsCnvSvc = ByteStreamCnvSvc()
-    eventSelector.ByteStreamInputSvc = bsInputSvc.name
-    eventPersistencySvc.CnvServices = [ bsCnvSvc.name ]
-    acc.addService( bsCnvSvc )
-
-    ROBDataProviderSvc=CompFactory.ROBDataProviderSvc
-    robDPSvc = ROBDataProviderSvc()
-    acc.addService( robDPSvc ) 
-
-    ByteStreamAddressProviderSvc=CompFactory.ByteStreamAddressProviderSvc
-    bsAddressProviderSvc = ByteStreamAddressProviderSvc(TypeNames=typeNames)
-    acc.addService( bsAddressProviderSvc )
-    
-    ProxyProviderSvc=CompFactory.ProxyProviderSvc
-
-    from AthenaServices.MetaDataSvcConfig import MetaDataSvcCfg
-    acc.merge(MetaDataSvcCfg(inputFlags, ["IOVDbMetaDataTool", "ByteStreamMetadataTool"]))
-    
-    proxy = ProxyProviderSvc()
-    proxy.ProviderNames += [ bsAddressProviderSvc.name ]
-    acc.addService( proxy )
-
-    return acc
-
-def ByteStreamWriteCfg( flags, typeNames=[] ):
-    acc = ComponentAccumulator("AthOutSeq")
+        event_selector = CompFactory.EventSelectorByteStream(
+            name="EventSelector",
+            Input=flags.Input.Files,
+            SkipEvents=flags.Exec.SkipEvents,
+            ByteStreamInputSvc=bytestream_input.name,
+        )
+        event_selector.HelperTools += [
+            CompFactory.xAODMaker.EventInfoSelectorTool()
+        ]
+        result.addService(event_selector)
+        result.setAppProperty("EvtSel", event_selector.name)
+
+    event_persistency = CompFactory.EvtPersistencySvc(
+        name="EventPersistencySvc", CnvServices=[bytestream_conversion.name]
+    )
+    result.addService(event_persistency)
+
+    result.addService(CompFactory.ROBDataProviderSvc())
+
+    address_provider = CompFactory.ByteStreamAddressProviderSvc(
+        TypeNames=type_names if type_names else list(),
+    )
+    result.addService(address_provider)
+
+    result.merge(
+        MetaDataSvcCfg(flags, ["IOVDbMetaDataTool", "ByteStreamMetadataTool"])
+    )
+
+    proxy = CompFactory.ProxyProviderSvc()
+    proxy.ProviderNames += [address_provider.name]
+    result.addService(proxy)
+
+    return result
+
+
+def ByteStreamWriteCfg(flags, type_names=[]):
+    result = ComponentAccumulator("AthOutSeq")
     outputSvc = CompFactory.ByteStreamEventStorageOutputSvc()
     outputSvc.MaxFileMB = 15000
     # event (beyond which it creates a new file)
@@ -73,34 +78,36 @@ def ByteStreamWriteCfg( flags, typeNames=[] ):
     outputSvc.OutputDirectory = "./"
     outputSvc.AppName = "Athena"
     # release variable depends the way the env is configured
-    #FileTag = release
+    # FileTag = release
     allRuns = set(flags.Input.RunNumber)
-    assert len(allRuns) == 1, "The input is from multiple runs, do not know which one to use {}".format(allRuns)
+    assert (
+        len(allRuns) == 1
+    ), "The input is from multiple runs, do not know which one to use {}".format(
+        allRuns
+    )
     outputSvc.RunNumber = allRuns.pop()
 
-    bsCnvSvc  = CompFactory.ByteStreamCnvSvc("ByteStreamCnvSvc")
-
-    bsCnvSvc.ByteStreamOutputSvcList = [ outputSvc.getName() ]
-    streamAlg = CompFactory.AthenaOutputStream( "BSOutputStreamAlg",
-                                                EvtConversionSvc = bsCnvSvc.getName(),
-                                                OutputFile = "ByteStreamEventStorageOutputSvc",
-                                                ItemList = typeNames )
+    bytestream_conversion = CompFactory.ByteStreamCnvSvc("ByteStreamCnvSvc")
 
-    acc.addService( outputSvc )
-    acc.addService( bsCnvSvc )
-    acc.addEventAlgo( streamAlg, primary = True )
-    return acc
+    bytestream_conversion.ByteStreamOutputSvcList = [outputSvc.getName()]
+    streamAlg = CompFactory.AthenaOutputStream(
+        "BSOutputStreamAlg",
+        EvtConversionSvc=bytestream_conversion.getName(),
+        OutputFile="ByteStreamEventStorageOutputSvc",
+        ItemList=type_names,
+    )
 
+    result.addService(outputSvc)
+    result.addService(bytestream_conversion)
+    result.addEventAlgo(streamAlg, primary=True)
+    return result
 
 
 if __name__ == "__main__":
-    from AthenaConfiguration.AllConfigFlags import ConfigFlags    
-    from AthenaConfiguration.TestDefaults import defaultTestFiles
-    from AthenaCommon.Configurable import Configurable
-    Configurable.configurableRun3Behavior=True
+    Configurable.configurableRun3Behavior = True
 
     ConfigFlags.Input.Files = defaultTestFiles.RAW
 
-    acc = ByteStreamReadCfg( ConfigFlags )
-    acc.store( open( "test.pkl", "wb" ) )
+    acc = ByteStreamReadCfg(ConfigFlags)
+    acc.store(open("test.pkl", "wb"))
     print("All OK")
diff --git a/TileCalorimeter/TileMonitoring/python/TileDQFragMonitorAlgorithm.py b/TileCalorimeter/TileMonitoring/python/TileDQFragMonitorAlgorithm.py
index f331a2014c195b921c92a082e9a340d8ec72a93e..ec65125a570e5d32d05fe7362cc14ab3c01edd6a 100644
--- a/TileCalorimeter/TileMonitoring/python/TileDQFragMonitorAlgorithm.py
+++ b/TileCalorimeter/TileMonitoring/python/TileDQFragMonitorAlgorithm.py
@@ -254,7 +254,7 @@ if __name__=='__main__':
 
     from ByteStreamCnvSvc.ByteStreamConfig import ByteStreamReadCfg
     tileTypeNames = ['TileRawChannelContainer/TileRawChannelCnt', 'TileDigitsContainer/TileDigitsCnt']
-    cfg.merge( ByteStreamReadCfg(ConfigFlags, typeNames = tileTypeNames) )
+    cfg.merge( ByteStreamReadCfg(ConfigFlags, type_names = tileTypeNames) )
 
     from TileRecUtils.TileRawChannelMakerConfig import TileRawChannelMakerCfg
     cfg.merge( TileRawChannelMakerCfg(ConfigFlags) )
diff --git a/TileCalorimeter/TileMonitoring/python/TileDigiNoiseMonitorAlgorithm.py b/TileCalorimeter/TileMonitoring/python/TileDigiNoiseMonitorAlgorithm.py
index 3e750d187f66399b5421a88dd5b62401c572e493..ac987ea30442c19f24eec878b67a0ae4265ed516 100644
--- a/TileCalorimeter/TileMonitoring/python/TileDigiNoiseMonitorAlgorithm.py
+++ b/TileCalorimeter/TileMonitoring/python/TileDigiNoiseMonitorAlgorithm.py
@@ -108,7 +108,7 @@ if __name__=='__main__':
 
     from ByteStreamCnvSvc.ByteStreamConfig import ByteStreamReadCfg
     tileTypeNames = ['TileRawChannelContainer/TileRawChannelCnt', 'TileDigitsContainer/TileDigitsCnt']
-    cfg.merge( ByteStreamReadCfg(ConfigFlags, typeNames = tileTypeNames) )
+    cfg.merge( ByteStreamReadCfg(ConfigFlags, type_names = tileTypeNames) )
 
     cfg.merge( TileDigiNoiseMonitoringConfig(ConfigFlags, TriggerChain = '') )
 
diff --git a/TileCalorimeter/TileMonitoring/python/TileRawChannelNoiseMonitorAlgorithm.py b/TileCalorimeter/TileMonitoring/python/TileRawChannelNoiseMonitorAlgorithm.py
index ae75099c21e8a8758caf657e8d209efa255fe133..0626765535c82ff712bc9b0b105da77be38905d4 100644
--- a/TileCalorimeter/TileMonitoring/python/TileRawChannelNoiseMonitorAlgorithm.py
+++ b/TileCalorimeter/TileMonitoring/python/TileRawChannelNoiseMonitorAlgorithm.py
@@ -121,7 +121,7 @@ if __name__=='__main__':
 
     from ByteStreamCnvSvc.ByteStreamConfig import ByteStreamReadCfg
     tileTypeNames = ['TileRawChannelContainer/TileRawChannelCnt', 'TileDigitsContainer/TileDigitsCnt']
-    cfg.merge( ByteStreamReadCfg(ConfigFlags, typeNames = tileTypeNames) )
+    cfg.merge( ByteStreamReadCfg(ConfigFlags, type_names = tileTypeNames) )
 
     from TileRecUtils.TileRawChannelMakerConfig import TileRawChannelMakerCfg
     cfg.merge( TileRawChannelMakerCfg(ConfigFlags) )
diff --git a/TileCalorimeter/TileMonitoring/python/TileRawChannelTimeMonitorAlgorithm.py b/TileCalorimeter/TileMonitoring/python/TileRawChannelTimeMonitorAlgorithm.py
index e0cb1adf8e7a0bb95da478f1a61c57940ff8fc7e..3f662248fbfcb6d29beb0e64bc81ec2a32c232a8 100644
--- a/TileCalorimeter/TileMonitoring/python/TileRawChannelTimeMonitorAlgorithm.py
+++ b/TileCalorimeter/TileMonitoring/python/TileRawChannelTimeMonitorAlgorithm.py
@@ -155,7 +155,7 @@ if __name__=='__main__':
     tileTypeNames = ['TileRawChannelContainer/TileRawChannelCnt',
                      'TileDigitsContainer/TileDigitsCnt',
                      'TileBeamElemContainer/TileBeamElemCnt']
-    cfg.merge( ByteStreamReadCfg(ConfigFlags, typeNames = tileTypeNames) )
+    cfg.merge( ByteStreamReadCfg(ConfigFlags, type_names = tileTypeNames) )
 
     from TileRecUtils.TileRawChannelMakerConfig import TileRawChannelMakerCfg
     cfg.merge( TileRawChannelMakerCfg(ConfigFlags) )
diff --git a/TileCalorimeter/TileRecAlgs/python/TileDigitsFilterConfig.py b/TileCalorimeter/TileRecAlgs/python/TileDigitsFilterConfig.py
index 97e1fd31c06c170a8fd6dd0bbc9b2ba27d545e2f..0542192fb2201ded04a335a29596a8ab4db7a511 100644
--- a/TileCalorimeter/TileRecAlgs/python/TileDigitsFilterConfig.py
+++ b/TileCalorimeter/TileRecAlgs/python/TileDigitsFilterConfig.py
@@ -78,7 +78,7 @@ if __name__ == "__main__":
 
     from ByteStreamCnvSvc.ByteStreamConfig import ByteStreamReadCfg
     tileTypeNames = ['TileRawChannelContainer/TileRawChannelCnt', 'TileDigitsContainer/TileDigitsCnt']
-    acc.merge( ByteStreamReadCfg(ConfigFlags, typeNames = tileTypeNames) )
+    acc.merge( ByteStreamReadCfg(ConfigFlags, type_names = tileTypeNames) )
 
     acc.merge( TileDigitsFilterOutputCfg(ConfigFlags) )
 
diff --git a/TileCalorimeter/TileSimAlgs/python/TileDigitsMakerConfig.py b/TileCalorimeter/TileSimAlgs/python/TileDigitsMakerConfig.py
index bf7398360ebdadd6647688e3a18e3aacfbc0785e..06070f59d8c289fea3fbfc21a97f58757276fef5 100644
--- a/TileCalorimeter/TileSimAlgs/python/TileDigitsMakerConfig.py
+++ b/TileCalorimeter/TileSimAlgs/python/TileDigitsMakerConfig.py
@@ -60,7 +60,7 @@ def TileDigitsMakerCfg(flags, **kwargs):
 
         if flags.Overlay.DataOverlay:
             from ByteStreamCnvSvc.ByteStreamConfig import ByteStreamReadCfg
-            acc.merge(ByteStreamReadCfg(flags, typeNames=[
+            acc.merge(ByteStreamReadCfg(flags, type_names=[
                 'TileDigitsContainer/' + flags.Overlay.BkgPrefix + 'TileDigitsCnt',
                 'TileRawChannelContainer/' + flags.Overlay.BkgPrefix + 'TileRawChannelCnt']
             ))