diff --git a/plugins/UM3NetworkPrinting/src/Cloud/CloudOutputDevice.py b/plugins/UM3NetworkPrinting/src/Cloud/CloudOutputDevice.py
index 0147851343..6e8ce73bf5 100644
--- a/plugins/UM3NetworkPrinting/src/Cloud/CloudOutputDevice.py
+++ b/plugins/UM3NetworkPrinting/src/Cloud/CloudOutputDevice.py
@@ -1,7 +1,7 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 from time import time
-from typing import List, Optional, Set, cast
+from typing import List, Optional, cast
 
 from PyQt5.QtCore import QObject, QUrl, pyqtProperty, pyqtSignal, pyqtSlot
 from PyQt5.QtGui import QDesktopServices
@@ -13,7 +13,6 @@ from UM.Logger import Logger
 from UM.Message import Message
 from UM.Scene.SceneNode import SceneNode
 from UM.Version import Version
-
 from cura.CuraApplication import CuraApplication
 from cura.PrinterOutput.NetworkedPrinterOutputDevice import AuthState
 from cura.PrinterOutput.PrinterOutputDevice import ConnectionType
diff --git a/plugins/UM3NetworkPrinting/src/Models/BaseModel.py b/plugins/UM3NetworkPrinting/src/Models/BaseModel.py
index 131b71ab43..3fb83c330f 100644
--- a/plugins/UM3NetworkPrinting/src/Models/BaseModel.py
+++ b/plugins/UM3NetworkPrinting/src/Models/BaseModel.py
@@ -1,4 +1,5 @@
-## Base model that maps kwargs to instance attributes.
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
 from datetime import datetime, timezone
 from typing import TypeVar, Dict, List, Any, Type, Union
 
diff --git a/plugins/UM3NetworkPrinting/src/Models/ClusterMaterial.py b/plugins/UM3NetworkPrinting/src/Models/ClusterMaterial.py
index 8687b015ce..31f5a39fac 100644
--- a/plugins/UM3NetworkPrinting/src/Models/ClusterMaterial.py
+++ b/plugins/UM3NetworkPrinting/src/Models/ClusterMaterial.py
@@ -1,4 +1,5 @@
-##  Class representing a material that was fetched from the cluster API.
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
 from .BaseModel import BaseModel
 
 
diff --git a/plugins/UM3NetworkPrinting/src/Models/Http/ClusterPrinterConfigurationMaterial.py b/plugins/UM3NetworkPrinting/src/Models/Http/ClusterPrinterConfigurationMaterial.py
index 1d0ef2b708..57e763e159 100644
--- a/plugins/UM3NetworkPrinting/src/Models/Http/ClusterPrinterConfigurationMaterial.py
+++ b/plugins/UM3NetworkPrinting/src/Models/Http/ClusterPrinterConfigurationMaterial.py
@@ -1,3 +1,5 @@
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
 from typing import Optional
 
 from UM.Logger import Logger
diff --git a/plugins/UM3NetworkPrinting/src/Models/LocalMaterial.py b/plugins/UM3NetworkPrinting/src/Models/LocalMaterial.py
index 9e606fd1c4..f3a67686cb 100644
--- a/plugins/UM3NetworkPrinting/src/Models/LocalMaterial.py
+++ b/plugins/UM3NetworkPrinting/src/Models/LocalMaterial.py
@@ -1,4 +1,5 @@
-##  Class representing a local material that was fetched from the container registry.
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
 from .BaseModel import BaseModel
 
 
diff --git a/plugins/UM3NetworkPrinting/src/Models/UM3PrintJobOutputModel.py b/plugins/UM3NetworkPrinting/src/Models/UM3PrintJobOutputModel.py
index 3462fc4a54..1a27fc3f73 100644
--- a/plugins/UM3NetworkPrinting/src/Models/UM3PrintJobOutputModel.py
+++ b/plugins/UM3NetworkPrinting/src/Models/UM3PrintJobOutputModel.py
@@ -15,7 +15,7 @@ class UM3PrintJobOutputModel(PrintJobOutputModel):
 
     def __init__(self, output_controller: PrinterOutputController, key: str = "", name: str = "", parent=None) -> None:
         super().__init__(output_controller, key, name, parent)
-        self._configuration_changes = []    # type: List[ConfigurationChangeModel]
+        self._configuration_changes = []  # type: List[ConfigurationChangeModel]
 
     @pyqtProperty("QVariantList", notify=configurationChangesChanged)
     def configurationChanges(self) -> List[ConfigurationChangeModel]:
diff --git a/plugins/UM3NetworkPrinting/src/Network/NetworkOutputDeviceManager.py b/plugins/UM3NetworkPrinting/src/Network/NetworkOutputDeviceManager.py
index 060d58ccdd..6bed02549f 100644
--- a/plugins/UM3NetworkPrinting/src/Network/NetworkOutputDeviceManager.py
+++ b/plugins/UM3NetworkPrinting/src/Network/NetworkOutputDeviceManager.py
@@ -10,8 +10,8 @@ from UM.Version import Version
 from cura.CuraApplication import CuraApplication
 from cura.PrinterOutput.PrinterOutputDevice import PrinterOutputDevice
 from cura.Settings.GlobalStack import GlobalStack
-from plugins.UM3NetworkPrinting.src.Network.ZeroConfClient import ZeroConfClient
 
+from .ZeroConfClient import ZeroConfClient
 from .ClusterApiClient import ClusterApiClient
 from .NetworkOutputDevice import NetworkOutputDevice
 
diff --git a/plugins/UM3NetworkPrinting/src/UltimakerNetworkedPrinterOutputDevice.py b/plugins/UM3NetworkPrinting/src/UltimakerNetworkedPrinterOutputDevice.py
index b098be629e..11977a9d10 100644
--- a/plugins/UM3NetworkPrinting/src/UltimakerNetworkedPrinterOutputDevice.py
+++ b/plugins/UM3NetworkPrinting/src/UltimakerNetworkedPrinterOutputDevice.py
@@ -1,6 +1,7 @@
 # Copyright (c) 2019 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 import os
+from abc import ABC
 from typing import List, Optional, Dict
 
 from PyQt5.QtCore import pyqtProperty, pyqtSignal, QObject, pyqtSlot, QUrl
@@ -22,7 +23,7 @@ from .Models.Http.ClusterPrintJobStatus import ClusterPrintJobStatus
 ## Output device class that forms the basis of Ultimaker networked printer output devices.
 #  Currently used for local networking and cloud printing using Ultimaker Connect.
 #  This base class primarily contains all the Qt properties and slots needed for the monitor page to work.
-class UltimakerNetworkedPrinterOutputDevice(NetworkedPrinterOutputDevice):
+class UltimakerNetworkedPrinterOutputDevice(NetworkedPrinterOutputDevice, ABC):
 
     # Signal emitted when the status of the print jobs for this cluster were changed over the network.
     printJobsChanged = pyqtSignal()
diff --git a/plugins/UM3NetworkPrinting/src/Utils.py b/plugins/UM3NetworkPrinting/src/Utils.py
index 410dd27d1d..8872576f8b 100644
--- a/plugins/UM3NetworkPrinting/src/Utils.py
+++ b/plugins/UM3NetworkPrinting/src/Utils.py
@@ -1,3 +1,5 @@
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
 from datetime import datetime, timedelta
 
 from UM import i18nCatalog