diff --git a/src/DIRAC/ConfigurationSystem/Client/CSAPI.py b/src/DIRAC/ConfigurationSystem/Client/CSAPI.py
index 2dbab567651..399fde278bd 100644
--- a/src/DIRAC/ConfigurationSystem/Client/CSAPI.py
+++ b/src/DIRAC/ConfigurationSystem/Client/CSAPI.py
@@ -5,16 +5,16 @@
 
 import datetime
 
-from DIRAC import gLogger, gConfig, S_OK, S_ERROR
+from DIRAC import S_ERROR, S_OK, gConfig, gLogger
 from DIRAC.ConfigurationSystem.Client.ConfigurationClient import ConfigurationClient
-from DIRAC.Core.Utilities import List
-from DIRAC.Core.Security.X509Chain import X509Chain  # pylint: disable=import-error
-from DIRAC.Core.Security import Locations
-from DIRAC.ConfigurationSystem.private.Modificator import Modificator
 from DIRAC.ConfigurationSystem.Client.Helpers import CSGlobals
 from DIRAC.ConfigurationSystem.Client.Helpers.Operations import Operations
-from DIRAC.ConfigurationSystem.Client.Helpers.Resources import getSites, getCESiteMapping
 from DIRAC.ConfigurationSystem.Client.Helpers.Path import cfgPath
+from DIRAC.ConfigurationSystem.Client.Helpers.Resources import getCESiteMapping, getSites
+from DIRAC.ConfigurationSystem.private.Modificator import Modificator
+from DIRAC.Core.Security import Locations
+from DIRAC.Core.Security.X509Chain import X509Chain  # pylint: disable=import-error
+from DIRAC.Core.Utilities import List
 
 
 class CSAPI:
diff --git a/src/DIRAC/Core/Security/VOMSService.py b/src/DIRAC/Core/Security/VOMSService.py
index e22bbd06c48..883d2533d99 100644
--- a/src/DIRAC/Core/Security/VOMSService.py
+++ b/src/DIRAC/Core/Security/VOMSService.py
@@ -37,27 +37,6 @@ def __init__(self, vo=None):
 
         self.userDict = None
 
-    def attGetUserNickname(self, dn, _ca=None):
-        """Get user nickname for a given DN if any
-
-        :param str dn: user DN
-        :param str _ca: CA, kept for backward compatibility
-        :return:  S_OK with Value: nickname
-        """
-
-        if self.userDict is None:
-            result = self.getUsers()
-            if not result["OK"]:
-                return result
-
-        uDict = self.userDict.get(dn)
-        if not uDict:
-            return S_ERROR(DErrno.EVOMS, "No nickname defined")
-        nickname = uDict.get("nickname")
-        if not nickname:
-            return S_ERROR(DErrno.EVOMS, "No nickname defined")
-        return S_OK(nickname)
-
     def getUsers(self):
         """Get all the users of the VOMS VO with their detailed information
 
diff --git a/src/DIRAC/Core/scripts/dirac_configure.py b/src/DIRAC/Core/scripts/dirac_configure.py
index 2d51abd6ca5..e381adf429b 100755
--- a/src/DIRAC/Core/scripts/dirac_configure.py
+++ b/src/DIRAC/Core/scripts/dirac_configure.py
@@ -44,6 +44,7 @@
 import os
 import sys
 import warnings
+
 import urllib3
 
 import DIRAC
@@ -235,9 +236,10 @@ def runConfigurationWizard(params):
     """Interactively configure DIRAC using metadata from installed extensions"""
     import subprocess
 
-    from DIRAC.Core.Utilities.Extensions import extensionsByPriority, getExtensionMetadata
     from prompt_toolkit import HTML, print_formatted_text, prompt
 
+    from DIRAC.Core.Utilities.Extensions import extensionsByPriority, getExtensionMetadata
+
     for extension in extensionsByPriority():
         extensionMetadata = getExtensionMetadata(extension)
         if extensionMetadata.get("primary_extension", False):
@@ -302,13 +304,14 @@ def main():
 
 
 def login(params):
+    from prompt_toolkit import HTML, print_formatted_text, prompt
+
     from DIRAC.FrameworkSystem.private.authorization.utils.Tokens import (
         getTokenFileLocation,
         readTokenFromFile,
         writeTokenDictToTokenFile,
     )
     from DIRAC.Resources.IdProvider.IdProviderFactory import IdProviderFactory
-    from prompt_toolkit import HTML, print_formatted_text, prompt
 
     # Init authorization client
     result = IdProviderFactory().getIdProvider("DIRACCLI", issuer=params.issuer, scope=" ")
diff --git a/src/DIRAC/DataManagementSystem/Agent/FTS3Agent.py b/src/DIRAC/DataManagementSystem/Agent/FTS3Agent.py
index 4151a3fffb8..cf21652750e 100644
--- a/src/DIRAC/DataManagementSystem/Agent/FTS3Agent.py
+++ b/src/DIRAC/DataManagementSystem/Agent/FTS3Agent.py
@@ -15,32 +15,30 @@
 import datetime
 import errno
 import os
-from urllib import parse
 import time
 
-# from threading import current_thread
-from multiprocessing.pool import ThreadPool
-
 # We use the dummy module because we use the ThreadPool
 from multiprocessing.dummy import current_process
-from socket import gethostname
-
-from DIRAC import S_OK, S_ERROR
 
+# from threading import current_thread
+from multiprocessing.pool import ThreadPool
+from socket import gethostname
+from urllib import parse
 
-from DIRAC.MonitoringSystem.Client.DataOperationSender import DataOperationSender
+from DIRAC import S_ERROR, S_OK
+from DIRAC.ConfigurationSystem.Client.Helpers.Operations import Operations as opHelper
+from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getDNForUsername
+from DIRAC.ConfigurationSystem.Client.Helpers.Resources import getFTS3ServerDict
 from DIRAC.Core.Base.AgentModule import AgentModule
 from DIRAC.Core.Utilities.DErrno import cmpError
 from DIRAC.Core.Utilities.DictCache import DictCache
 from DIRAC.Core.Utilities.TimeUtilities import fromString
-from DIRAC.ConfigurationSystem.Client.Helpers.Resources import getFTS3ServerDict
-from DIRAC.ConfigurationSystem.Client.Helpers.Operations import Operations as opHelper
-from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getDNForUsername
+from DIRAC.DataManagementSystem.Client.FTS3Job import FTS3Job
+from DIRAC.DataManagementSystem.DB.FTS3DB import FTS3DB
+from DIRAC.DataManagementSystem.private import FTS3Utilities
 from DIRAC.FrameworkSystem.Client.Logger import gLogger
 from DIRAC.FrameworkSystem.Client.ProxyManagerClient import gProxyManager
-from DIRAC.DataManagementSystem.private import FTS3Utilities
-from DIRAC.DataManagementSystem.DB.FTS3DB import FTS3DB
-from DIRAC.DataManagementSystem.Client.FTS3Job import FTS3Job
+from DIRAC.MonitoringSystem.Client.DataOperationSender import DataOperationSender
 from DIRAC.RequestManagementSystem.Client.ReqClient import ReqClient
 
 # pylint: disable=attribute-defined-outside-init
diff --git a/src/DIRAC/DataManagementSystem/Service/FTS3ManagerHandler.py b/src/DIRAC/DataManagementSystem/Service/FTS3ManagerHandler.py
index 989ee7c0403..91992f6e387 100644
--- a/src/DIRAC/DataManagementSystem/Service/FTS3ManagerHandler.py
+++ b/src/DIRAC/DataManagementSystem/Service/FTS3ManagerHandler.py
@@ -8,16 +8,13 @@
   :caption: FTS3Manager options
 
 """
-from DIRAC import S_OK, S_ERROR, gLogger
+from DIRAC import S_ERROR, S_OK, gLogger
 from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getDNForUsername
 from DIRAC.Core.DISET.RequestHandler import RequestHandler, getServiceOption
 from DIRAC.Core.Security.Properties import FULL_DELEGATION, LIMITED_DELEGATION
 from DIRAC.Core.Utilities import DErrno
-from DIRAC.Core.Utilities.JEncode import strToIntDict
-
-
+from DIRAC.Core.Utilities.JEncode import decode, encode, strToIntDict
 from DIRAC.DataManagementSystem.DB.FTS3DB import FTS3DB
-from DIRAC.Core.Utilities.JEncode import encode, decode
 
 ########################################################################
 
diff --git a/src/DIRAC/FrameworkSystem/Client/ComponentInstaller.py b/src/DIRAC/FrameworkSystem/Client/ComponentInstaller.py
index de66319d961..8498afb398a 100644
--- a/src/DIRAC/FrameworkSystem/Client/ComponentInstaller.py
+++ b/src/DIRAC/FrameworkSystem/Client/ComponentInstaller.py
@@ -64,7 +64,6 @@
 import MySQLdb
 from diraccfg import CFG
 from prompt_toolkit import prompt
-from typing import cast
 
 import DIRAC
 from DIRAC import gConfig, gLogger, rootPath
@@ -85,10 +84,10 @@
     JOB_ADMINISTRATOR,
     NORMAL_USER,
     OPERATOR,
+    PRODUCTION_MANAGEMENT,
     PROXY_MANAGEMENT,
     SERVICE_ADMINISTRATOR,
     TRUSTED_HOST,
-    PRODUCTION_MANAGEMENT,
 )
 from DIRAC.Core.Utilities.Extensions import (
     extensionsByPriority,
diff --git a/src/DIRAC/FrameworkSystem/Service/TornadoTokenManagerHandler.py b/src/DIRAC/FrameworkSystem/Service/TornadoTokenManagerHandler.py
index f15d2415136..41da31e61ff 100644
--- a/src/DIRAC/FrameworkSystem/Service/TornadoTokenManagerHandler.py
+++ b/src/DIRAC/FrameworkSystem/Service/TornadoTokenManagerHandler.py
@@ -31,22 +31,21 @@
 
 import pprint
 
-from DIRAC import S_OK, S_ERROR
+from DIRAC import S_ERROR, S_OK
+from DIRAC.ConfigurationSystem.Client.Helpers import Registry
 from DIRAC.Core.Security import Properties
+from DIRAC.Core.Tornado.Server.TornadoService import TornadoService
 from DIRAC.Core.Utilities import ThreadSafe
 from DIRAC.Core.Utilities.DictCache import DictCache
-from DIRAC.Core.Tornado.Server.TornadoService import TornadoService
 from DIRAC.FrameworkSystem.DB.TokenDB import TokenDB
-from DIRAC.ConfigurationSystem.Client.Helpers import Registry
-from DIRAC.Resources.IdProvider.IdProviderFactory import IdProviderFactory
 from DIRAC.FrameworkSystem.Utilities.TokenManagementUtilities import (
-    getIdProviderClient,
+    DEFAULT_AT_EXPIRATION_TIME,
+    DEFAULT_RT_EXPIRATION_TIME,
     getCachedKey,
     getCachedToken,
-    DEFAULT_RT_EXPIRATION_TIME,
-    DEFAULT_AT_EXPIRATION_TIME,
+    getIdProviderClient,
 )
-
+from DIRAC.Resources.IdProvider.IdProviderFactory import IdProviderFactory
 
 # Used to synchronize the cache with user tokens
 gTokensSync = ThreadSafe.Synchronizer()
diff --git a/src/DIRAC/FrameworkSystem/scripts/dirac_login.py b/src/DIRAC/FrameworkSystem/scripts/dirac_login.py
index 5e503ebe72b..0c68987da88 100644
--- a/src/DIRAC/FrameworkSystem/scripts/dirac_login.py
+++ b/src/DIRAC/FrameworkSystem/scripts/dirac_login.py
@@ -13,44 +13,41 @@
   # Return token
   $ dirac-login dirac_user --token
 """
+import copy
 import os
 import sys
-import copy
-import datetime
-import json
-from pathlib import Path
-from prompt_toolkit import prompt, print_formatted_text as print, HTML
+
+from prompt_toolkit import HTML, prompt
+from prompt_toolkit import print_formatted_text as print
 
 import DIRAC
-from DIRAC import gConfig, gLogger, S_OK, S_ERROR
-from DIRAC.Core.Security.Locations import getDefaultProxyLocation, getCertificateAndKeyLocation
-from DIRAC.Core.Security.VOMS import VOMS
+from DIRAC import S_ERROR, S_OK, gConfig, gLogger
+from DIRAC.Core.Base.Script import Script
 from DIRAC.Core.Security.DiracX import addTokenToPEM
+from DIRAC.Core.Security.Locations import getCertificateAndKeyLocation, getDefaultProxyLocation
 from DIRAC.Core.Security.ProxyFile import writeToProxyFile
-from DIRAC.Core.Security.ProxyInfo import getProxyInfo, formatProxyInfoAsString
+from DIRAC.Core.Security.ProxyInfo import formatProxyInfoAsString, getProxyInfo
+from DIRAC.Core.Security.VOMS import VOMS
 from DIRAC.Core.Security.X509Chain import X509Chain  # pylint: disable=import-error
-from DIRAC.Core.Base.Script import Script
-from DIRAC.Core.Base.Client import Client
-
 
 # At this point, we disable CS synchronization so that an error related
 # to the lack of a proxy certificate does not occur when trying to synchronize.
 # Synchronization will take place after passing the authorization algorithm (creating a proxy).
 Script.disableCS()
 
-from DIRAC.Resources.IdProvider.IdProviderFactory import IdProviderFactory
-from DIRAC.FrameworkSystem.Client.ProxyManagerClient import gProxyManager
-from DIRAC.FrameworkSystem.private.authorization.utils.Tokens import (
-    writeTokenDictToTokenFile,
-    readTokenFromFile,
-    getTokenFileLocation,
-)
 from DIRAC.ConfigurationSystem.Client.Helpers.Registry import (
+    findDefaultGroupForDN,
     getGroupOption,
     getVOMSAttributeForGroup,
     getVOMSVOForGroup,
-    findDefaultGroupForDN,
 )
+from DIRAC.FrameworkSystem.Client.ProxyManagerClient import gProxyManager
+from DIRAC.FrameworkSystem.private.authorization.utils.Tokens import (
+    getTokenFileLocation,
+    readTokenFromFile,
+    writeTokenDictToTokenFile,
+)
+from DIRAC.Resources.IdProvider.IdProviderFactory import IdProviderFactory
 
 # This value shows what authorization way will be by default
 DEFAULT_AUTH_WAY = "certificate"  # possible values are "certificate", "diracas"
diff --git a/src/DIRAC/FrameworkSystem/scripts/dirac_proxy_destroy.py b/src/DIRAC/FrameworkSystem/scripts/dirac_proxy_destroy.py
index 7441fa35ae4..2fd8e6a5719 100755
--- a/src/DIRAC/FrameworkSystem/scripts/dirac_proxy_destroy.py
+++ b/src/DIRAC/FrameworkSystem/scripts/dirac_proxy_destroy.py
@@ -8,13 +8,12 @@
 import os
 
 import DIRAC
-from DIRAC import gLogger, S_OK
+from DIRAC import S_OK, gLogger
+from DIRAC.ConfigurationSystem.Client.Helpers import Registry
+from DIRAC.Core.Base.Client import Client
 from DIRAC.Core.Base.Script import Script
-
 from DIRAC.Core.Security import Locations, ProxyInfo
-from DIRAC.Core.Base.Client import Client
 from DIRAC.FrameworkSystem.Client.ProxyManagerClient import gProxyManager
-from DIRAC.ConfigurationSystem.Client.Helpers import Registry
 
 
 class Params:
diff --git a/src/DIRAC/FrameworkSystem/scripts/dirac_proxy_get_uploaded_info.py b/src/DIRAC/FrameworkSystem/scripts/dirac_proxy_get_uploaded_info.py
index a10f98496a4..cb9cac5cd81 100755
--- a/src/DIRAC/FrameworkSystem/scripts/dirac_proxy_get_uploaded_info.py
+++ b/src/DIRAC/FrameworkSystem/scripts/dirac_proxy_get_uploaded_info.py
@@ -17,12 +17,12 @@
 """
 import sys
 
-from DIRAC import gLogger, S_OK
+from DIRAC import S_OK, gLogger
+from DIRAC.ConfigurationSystem.Client.Helpers import Registry
 from DIRAC.Core.Base.Script import Script
-from DIRAC.FrameworkSystem.Client.ProxyManagerClient import ProxyManagerClient
 from DIRAC.Core.Security import Properties
 from DIRAC.Core.Security.ProxyInfo import getProxyInfo
-from DIRAC.ConfigurationSystem.Client.Helpers import Registry
+from DIRAC.FrameworkSystem.Client.ProxyManagerClient import ProxyManagerClient
 
 userName = False
 
diff --git a/src/DIRAC/Interfaces/API/DiracAdmin.py b/src/DIRAC/Interfaces/API/DiracAdmin.py
index 2d9905f5e66..a04f6586973 100755
--- a/src/DIRAC/Interfaces/API/DiracAdmin.py
+++ b/src/DIRAC/Interfaces/API/DiracAdmin.py
@@ -90,7 +90,7 @@ def checkProxyUploaded(self, userDN, userGroup, requiredTime):
 
         Example usage:
 
-          >>> gLogger.notice(diracAdmin.setProxyPersistency( 'some DN', 'dirac group', True ))
+          >>> gLogger.notice(diracAdmin.checkProxyUploaded( 'some DN', 'dirac group', True ))
           {'OK': True, 'Value' : True/False }
 
         :param userDN: User DN
diff --git a/src/DIRAC/Interfaces/Utilities/DCommands.py b/src/DIRAC/Interfaces/Utilities/DCommands.py
index d7f2f8226b6..867436c763b 100644
--- a/src/DIRAC/Interfaces/Utilities/DCommands.py
+++ b/src/DIRAC/Interfaces/Utilities/DCommands.py
@@ -1,27 +1,26 @@
 #!/usr/bin/env python
+import glob
+import json
 import os.path
+import random
 import re
-import uuid
 import stat
-import json
-import random
-import glob
 import time
-from configparser import ConfigParser, NoSectionError, NoOptionError
+import uuid
+from configparser import ConfigParser, NoOptionError, NoSectionError
 
 import DIRAC
 import DIRAC.Core.Security.ProxyInfo as ProxyInfo
 import DIRAC.FrameworkSystem.Client.ProxyGeneration as ProxyGeneration
-from DIRAC import S_OK, S_ERROR, gConfig, gLogger
-from DIRAC.Core.Security.Locations import getCAsLocation
-from DIRAC.Core.Security import Locations, VOMS
+from DIRAC import S_ERROR, S_OK, gConfig, gLogger
+from DIRAC.ConfigurationSystem.Client.Helpers import Registry
+from DIRAC.Core.Security import VOMS, Locations
 from DIRAC.Core.Security.DiracX import addTokenToPEM
+from DIRAC.Core.Security.Locations import getCAsLocation
 from DIRAC.Core.Utilities.PrettyPrint import printTable
 from DIRAC.FrameworkSystem.Client.BundleDeliveryClient import BundleDeliveryClient
-from DIRAC.ConfigurationSystem.Client.Helpers import Registry
 from DIRAC.Resources.Catalog.FileCatalog import FileCatalog
 
-
 # -----------------------------
 # Proxy manipulation functions
 # -----------------------------
@@ -530,16 +529,6 @@ def addVomsExt(self, proxy):
         chain = result["Value"]
         chain.dumpAllToFile(proxy)
 
-    def checkProxyOrInit(self):
-        create = False
-        try:
-            create = not self.proxyIsValid()
-        except:
-            create = True
-
-        if create:
-            self.proxyInit()
-
     def getUserName(self):
         proxyPath = _getProxyLocation()
         if not proxyPath:
@@ -601,28 +590,6 @@ def guessConfigFromCS(config, section, userName, groupName):
                 config.set(section, "default_se", defaultSESite)
 
 
-def sessionFromProxy(config=None, sessionDir=None):
-    session = DSession(None, config, sessionDir=sessionDir)
-    # force copy of config profile options to environment
-    session.copyProfile()
-    return session
-
-
-def getDNFromProxy():
-    proxyPath = _getProxyLocation()
-    if not proxyPath:
-        gLogger.error("No proxy found")
-        return None
-
-    retVal = _getProxyInfo(proxyPath)
-    if not retVal["OK"]:
-        return retVal
-
-    pi = retVal["Value"]
-
-    return S_OK(pi["identity"])
-
-
 # -------------------------
 # DCommands FC/LFN helpers
 # -------------------------
diff --git a/src/DIRAC/Interfaces/scripts/dconfig.py b/src/DIRAC/Interfaces/scripts/dconfig.py
index f44e2ed7a9d..92a2d4502a7 100755
--- a/src/DIRAC/Interfaces/scripts/dconfig.py
+++ b/src/DIRAC/Interfaces/scripts/dconfig.py
@@ -7,14 +7,12 @@
     $ dconfig (lists contents of ~/dirac/dcommands.conf)
 """
 import DIRAC
-from DIRAC import gLogger, S_OK
+from DIRAC import S_OK, gLogger
 from DIRAC.Core.Base.Script import Script
-
 from DIRAC.Interfaces.Utilities.DCommands import (
     DConfig,
     createMinimalConfig,
 )
-from DIRAC.Interfaces.Utilities.DCommands import getDNFromProxy
 
 
 class Params:
@@ -77,7 +75,7 @@ def main():
         else:
             section = arg
 
-        if value != None:
+        if value is not None:
             dconfig.set(section, option, value)
             modified = True
         else:
diff --git a/src/DIRAC/Interfaces/scripts/dirac_admin_sync_users_from_file.py b/src/DIRAC/Interfaces/scripts/dirac_admin_sync_users_from_file.py
index 675c8d51e16..cd4b2343ed1 100755
--- a/src/DIRAC/Interfaces/scripts/dirac_admin_sync_users_from_file.py
+++ b/src/DIRAC/Interfaces/scripts/dirac_admin_sync_users_from_file.py
@@ -41,7 +41,7 @@ def main():
         usersCFG = CFG().loadFromFile(args[0])
     except Exception as e:
         errorList.append(("file open", f"Can't parse file {args[0]}: {str(e)}"))
-        errorCode = 1
+        exitCode = 1
     else:
         if not diracAdmin.csSyncUsersWithCFG(usersCFG):
             errorList.append(("modify users", f"Cannot sync with {args[0]}"))
diff --git a/src/DIRAC/RequestManagementSystem/private/OperationHandlerBase.py b/src/DIRAC/RequestManagementSystem/private/OperationHandlerBase.py
index 3278e8b27cb..f4cd288849d 100644
--- a/src/DIRAC/RequestManagementSystem/private/OperationHandlerBase.py
+++ b/src/DIRAC/RequestManagementSystem/private/OperationHandlerBase.py
@@ -33,9 +33,9 @@
 
 import os
 
-from DIRAC import gLogger, gConfig, S_ERROR, S_OK
+from DIRAC import S_ERROR, S_OK, gConfig, gLogger
 from DIRAC.ConfigurationSystem.Client.Helpers.Operations import Operations
-from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getGroupsWithVOMSAttribute, getDNForUsername
+from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getDNForUsername, getGroupsWithVOMSAttribute
 from DIRAC.Core.Utilities import Network, TimeUtilities
 from DIRAC.Core.Utilities.ReturnValues import returnSingleResult
 from DIRAC.DataManagementSystem.Client.DataManager import DataManager
diff --git a/src/DIRAC/Resources/Computing/CloudComputingElement.py b/src/DIRAC/Resources/Computing/CloudComputingElement.py
index e98f9b5aec9..6ba416b0a15 100644
--- a/src/DIRAC/Resources/Computing/CloudComputingElement.py
+++ b/src/DIRAC/Resources/Computing/CloudComputingElement.py
@@ -147,24 +147,23 @@
 
 """
 
-import uuid
+import configparser
+import datetime
 import os
 import sys
+import uuid
+from email.mime.multipart import MIMEMultipart
+from email.mime.text import MIMEText
+
 import yaml
-import configparser
-import datetime
-from libcloud.compute.types import Provider, NodeState
 from libcloud.compute.providers import get_driver, set_driver
-from email.mime.text import MIMEText
-from email.mime.multipart import MIMEMultipart
+from libcloud.compute.types import NodeState, Provider
 
-from DIRAC import S_OK, S_ERROR, gConfig, rootPath
-from DIRAC.Resources.Computing.ComputingElement import ComputingElement
-from DIRAC.Core.Security.ProxyInfo import getProxyInfo
-from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getVOForGroup
+from DIRAC import S_ERROR, S_OK, rootPath
 from DIRAC.ConfigurationSystem.Client.Helpers.Operations import Operations
-from DIRAC.FrameworkSystem.Client.ProxyManagerClient import ProxyManagerClient
-from DIRAC.FrameworkSystem.Client.ProxyManagerClient import gProxyManager
+from DIRAC.Core.Security.ProxyInfo import getProxyInfo
+from DIRAC.FrameworkSystem.Client.ProxyManagerClient import ProxyManagerClient, gProxyManager
+from DIRAC.Resources.Computing.ComputingElement import ComputingElement
 
 # Standard CE name
 CE_NAME = "CloudCE"
diff --git a/src/DIRAC/TransformationSystem/Client/RequestTasks.py b/src/DIRAC/TransformationSystem/Client/RequestTasks.py
index 900d64f3e6d..69052d91a63 100644
--- a/src/DIRAC/TransformationSystem/Client/RequestTasks.py
+++ b/src/DIRAC/TransformationSystem/Client/RequestTasks.py
@@ -1,14 +1,13 @@
 import time
 
-from DIRAC import S_OK, S_ERROR, gLogger
-
+from DIRAC import S_ERROR, S_OK, gLogger
 from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getDNForUsername
 from DIRAC.Core.Security.ProxyInfo import getProxyInfo
 from DIRAC.Core.Utilities.JEncode import decode
+from DIRAC.RequestManagementSystem.Client.File import File
+from DIRAC.RequestManagementSystem.Client.Operation import Operation
 from DIRAC.RequestManagementSystem.Client.ReqClient import ReqClient
 from DIRAC.RequestManagementSystem.Client.Request import Request
-from DIRAC.RequestManagementSystem.Client.Operation import Operation
-from DIRAC.RequestManagementSystem.Client.File import File
 from DIRAC.RequestManagementSystem.private.RequestValidator import RequestValidator
 from DIRAC.TransformationSystem.Client import TransformationFilesStatus
 from DIRAC.TransformationSystem.Client.BodyPlugin.BaseBody import BaseBody
diff --git a/src/DIRAC/WorkloadManagementSystem/Agent/PilotLoggingAgent.py b/src/DIRAC/WorkloadManagementSystem/Agent/PilotLoggingAgent.py
index 44708e9ab44..bef36abc719 100644
--- a/src/DIRAC/WorkloadManagementSystem/Agent/PilotLoggingAgent.py
+++ b/src/DIRAC/WorkloadManagementSystem/Agent/PilotLoggingAgent.py
@@ -11,17 +11,16 @@
 
 # # imports
 import os
-import time
 import tempfile
-from DIRAC import S_OK, S_ERROR, gConfig
+import time
+
+from DIRAC import S_ERROR, S_OK
 from DIRAC.ConfigurationSystem.Client.Helpers.Operations import Operations
-from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getVOs
+from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getDNForUsername, getVOMSAttributeForGroup, getVOs
 from DIRAC.Core.Base.AgentModule import AgentModule
 from DIRAC.Core.Security.ProxyInfo import getProxyInfo
-from DIRAC.Core.Utilities.Proxy import executeWithoutServerCertificate
-from DIRAC.Core.Utilities.Proxy import getProxy
+from DIRAC.Core.Utilities.Proxy import executeWithoutServerCertificate, getProxy
 from DIRAC.DataManagementSystem.Client.DataManager import DataManager
-from DIRAC.ConfigurationSystem.Client.Helpers.Registry import getVOMSAttributeForGroup, getDNForUsername
 from DIRAC.WorkloadManagementSystem.Client.TornadoPilotLoggingClient import TornadoPilotLoggingClient
 
 
diff --git a/src/DIRAC/WorkloadManagementSystem/Agent/test/Test_Agent_PilotLoggingAgent.py b/src/DIRAC/WorkloadManagementSystem/Agent/test/Test_Agent_PilotLoggingAgent.py
index 8bf566199ac..23adff9854d 100644
--- a/src/DIRAC/WorkloadManagementSystem/Agent/test/Test_Agent_PilotLoggingAgent.py
+++ b/src/DIRAC/WorkloadManagementSystem/Agent/test/Test_Agent_PilotLoggingAgent.py
@@ -46,7 +46,6 @@ def plaBase(mocker):
         "DIRAC.WorkloadManagementSystem.Agent.PilotLoggingAgent.getVOs",
         return_value={"OK": True, "Value": ["gridpp", "lz"]},
     )
-    mocker.patch("DIRAC.WorkloadManagementSystem.Agent.PilotLoggingAgent.gConfig.getValue", return_value="GridPP")
     mocker.patch("DIRAC.WorkloadManagementSystem.Agent.PilotLoggingAgent.Operations.getValue", side_effect=mockReply)
     mocker.patch(
         "DIRAC.WorkloadManagementSystem.Agent.PilotLoggingAgent.Operations.getOptionsDict", side_effect=mockReply1
diff --git a/src/DIRAC/WorkloadManagementSystem/DB/JobDB.py b/src/DIRAC/WorkloadManagementSystem/DB/JobDB.py
index f52618817a3..cc819b329b7 100755
--- a/src/DIRAC/WorkloadManagementSystem/DB/JobDB.py
+++ b/src/DIRAC/WorkloadManagementSystem/DB/JobDB.py
@@ -1338,18 +1338,18 @@ def getAllSiteMaskStatus(self):
         return S_OK(siteDict)
 
     #############################################################################
-    def setSiteMask(self, siteMaskList, authorDN="Unknown", comment="No comment"):
+    def setSiteMask(self, siteMaskList, author="Unknown", comment="No comment"):
         """Set the Site Mask to the given mask in a form of a list of tuples (site,status)"""
 
         for site, status in siteMaskList:
-            result = self.__setSiteStatusInMask(site, status, authorDN, comment)
+            result = self.__setSiteStatusInMask(site, status, author, comment)
             if not result["OK"]:
                 return result
 
         return S_OK()
 
     #############################################################################
-    def __setSiteStatusInMask(self, site, status, authorDN="Unknown", comment="No comment"):
+    def __setSiteStatusInMask(self, site, status, author="Unknown", comment="No comment"):
         """Set the given site status to 'status' or add a new active site"""
 
         result = self._escapeString(site)
@@ -1362,10 +1362,10 @@ def __setSiteStatusInMask(self, site, status, authorDN="Unknown", comment="No co
             return result
         status = result["Value"]
 
-        result = self._escapeString(authorDN)
+        result = self._escapeString(author)
         if not result["OK"]:
             return result
-        authorDN = result["Value"]
+        author = result["Value"]
 
         result = self._escapeString(comment)
         if not result["OK"]:
@@ -1384,14 +1384,14 @@ def __setSiteStatusInMask(self, site, status, authorDN="Unknown", comment="No co
                         "UPDATE SiteMask SET Status=%s,LastUpdateTime=UTC_TIMESTAMP(),"
                         "Author=%s, Comment=%s WHERE Site=%s"
                     )
-                    req = req % (status, authorDN, comment, site)
+                    req = req % (status, author, comment, site)
             else:
-                req = f"INSERT INTO SiteMask VALUES ({site},{status},UTC_TIMESTAMP(),{authorDN},{comment})"
+                req = f"INSERT INTO SiteMask VALUES ({site},{status},UTC_TIMESTAMP(),{author},{comment})"
             result = self._update(req)
             if not result["OK"]:
                 return S_ERROR("Failed to update the Site Mask")
             # update the site mask logging record
-            req = f"INSERT INTO SiteMaskLogging VALUES ({site},{status},UTC_TIMESTAMP(),{authorDN},{comment})"
+            req = f"INSERT INTO SiteMaskLogging VALUES ({site},{status},UTC_TIMESTAMP(),{author},{comment})"
             result = self._update(req)
             if not result["OK"]:
                 self.log.warn("Failed to update site mask logging", f"for {site}")
@@ -1401,16 +1401,16 @@ def __setSiteStatusInMask(self, site, status, authorDN="Unknown", comment="No co
         return S_OK()
 
     #############################################################################
-    def banSiteInMask(self, site, authorDN="Unknown", comment="No comment"):
+    def banSiteInMask(self, site, author="Unknown", comment="No comment"):
         """Forbid the given site in the Site Mask"""
 
-        return self.__setSiteStatusInMask(site, "Banned", authorDN, comment)
+        return self.__setSiteStatusInMask(site, "Banned", author, comment)
 
     #############################################################################
-    def allowSiteInMask(self, site, authorDN="Unknown", comment="No comment"):
+    def allowSiteInMask(self, site, author="Unknown", comment="No comment"):
         """Forbid the given site in the Site Mask"""
 
-        return self.__setSiteStatusInMask(site, "Active", authorDN, comment)
+        return self.__setSiteStatusInMask(site, "Active", author, comment)
 
     #############################################################################
     def removeSiteFromMask(self, site=None):
diff --git a/src/DIRAC/WorkloadManagementSystem/DB/SandboxMetadataDB.py b/src/DIRAC/WorkloadManagementSystem/DB/SandboxMetadataDB.py
index 20e12bc6009..cdd778a2f80 100644
--- a/src/DIRAC/WorkloadManagementSystem/DB/SandboxMetadataDB.py
+++ b/src/DIRAC/WorkloadManagementSystem/DB/SandboxMetadataDB.py
@@ -375,7 +375,7 @@ def getSandboxOwner(self, SEName, SEPFN, requesterDN, requesterGroup):
 
         :param SEName: name of the StorageElement
         :param SEPFN: PFN of the Sandbox
-        :param requestDN: host DN used as credentials
+        :param requesterDN: host DN used as credentials
         :param requesterGroup: group used to use as credentials (should be 'hosts')
 
         :returns: S_OK with tuple (owner, ownerGroup)
diff --git a/src/DIRAC/WorkloadManagementSystem/Service/JobPolicy.py b/src/DIRAC/WorkloadManagementSystem/Service/JobPolicy.py
index 81b34ff6f70..c200bc834de 100755
--- a/src/DIRAC/WorkloadManagementSystem/Service/JobPolicy.py
+++ b/src/DIRAC/WorkloadManagementSystem/Service/JobPolicy.py
@@ -5,7 +5,6 @@
 from DIRAC.ConfigurationSystem.Client.Helpers.Registry import (
     getGroupsForUser,
     getPropertiesForGroup,
-    getUsernameForDN,
     getUsersInGroup,
 )
 from DIRAC.Core.Security import Properties
diff --git a/src/DIRAC/WorkloadManagementSystem/Service/WMSAdministratorHandler.py b/src/DIRAC/WorkloadManagementSystem/Service/WMSAdministratorHandler.py
index eb43dda6910..e64c88efd3f 100755
--- a/src/DIRAC/WorkloadManagementSystem/Service/WMSAdministratorHandler.py
+++ b/src/DIRAC/WorkloadManagementSystem/Service/WMSAdministratorHandler.py
@@ -50,7 +50,7 @@ def export_setSiteMask(self, siteList):
         """
         credDict = self.getRemoteCredentials()
         maskList = [(site, "Active") for site in siteList]
-        return self.jobDB.setSiteMask(maskList, credDict["DN"], "No comment")
+        return self.jobDB.setSiteMask(maskList, credDict["username"], "No comment")
 
     ##############################################################################
     types_getSiteMask = []
@@ -101,7 +101,7 @@ def export_banSite(self, site, comment="No comment"):
         :return: S_OK()/S_ERROR()
         """
         credDict = self.getRemoteCredentials()
-        author = credDict["username"] if credDict["username"] != "anonymous" else credDict["DN"]
+        author = credDict["username"] if credDict["username"] != "anonymous" else credDict["username"]
         return self.jobDB.banSiteInMask(site, author, comment)
 
     ##############################################################################
@@ -116,7 +116,7 @@ def export_allowSite(self, site, comment="No comment"):
         :return: S_OK()/S_ERROR()
         """
         credDict = self.getRemoteCredentials()
-        author = credDict["username"] if credDict["username"] != "anonymous" else credDict["DN"]
+        author = credDict["username"] if credDict["username"] != "anonymous" else credDict["username"]
         return self.jobDB.allowSiteInMask(site, author, comment)
 
     ##############################################################################