diff --git a/cura/PrinterOutput/FirmwareUpdater.py b/cura/PrinterOutput/FirmwareUpdater.py
index 06e019c593..2f200118a9 100644
--- a/cura/PrinterOutput/FirmwareUpdater.py
+++ b/cura/PrinterOutput/FirmwareUpdater.py
@@ -9,7 +9,7 @@ from cura.CuraApplication import CuraApplication
 
 from enum import IntEnum
 from threading import Thread
-from typing import Any
+from typing import Union
 
 class FirmwareUpdater(QObject):
     firmwareProgressChanged = pyqtSignal()
@@ -25,7 +25,7 @@ class FirmwareUpdater(QObject):
         self._firmware_progress = 0
         self._firmware_update_state = FirmwareUpdateState.idle
 
-    def updateFirmware(self, file: Any[str, QUrl]) -> None:
+    def updateFirmware(self, file: Union[str, QUrl]) -> None:
         # the file path could be url-encoded.
         if file.startswith("file://"):
             self._firmware_location = QUrl(file).toLocalFile()
@@ -60,7 +60,7 @@ class FirmwareUpdater(QObject):
         return self._firmware_progress
 
     @pyqtProperty(int, notify=firmwareUpdateStateChanged)
-    def firmwareUpdateState(self) -> FirmwareUpdateState:
+    def firmwareUpdateState(self) -> "FirmwareUpdateState":
         return self._firmware_update_state
 
     def setFirmwareUpdateState(self, state) -> None:
diff --git a/cura/PrinterOutput/GenericOutputController.py b/cura/PrinterOutput/GenericOutputController.py
index e6310e5bff..e26fefb520 100644
--- a/cura/PrinterOutput/GenericOutputController.py
+++ b/cura/PrinterOutput/GenericOutputController.py
@@ -1,7 +1,7 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Union
 
 from cura.PrinterOutput.PrinterOutputController import PrinterOutputController
 from PyQt5.QtCore import QTimer
@@ -109,7 +109,7 @@ class GenericOutputController(PrinterOutputController):
         self.setTargetBedTemperature(self._preheat_printer, 0)
         self._preheat_printer.updateIsPreheating(False)
 
-    def setTargetHotendTemperature(self, printer: "PrinterOutputModel", position: int, temperature: int):
+    def setTargetHotendTemperature(self, printer: "PrinterOutputModel", position: int, temperature: Union[int, float]) -> None:
         self._output_device.sendCommand("M104 S%s T%s" % (temperature, position))
 
     def _onTargetHotendTemperatureChanged(self):
diff --git a/cura/PrinterOutput/PrintJobOutputModel.py b/cura/PrinterOutput/PrintJobOutputModel.py
index 5b8cc39ad8..70878a7573 100644
--- a/cura/PrinterOutput/PrintJobOutputModel.py
+++ b/cura/PrinterOutput/PrintJobOutputModel.py
@@ -91,7 +91,7 @@ class PrintJobOutputModel(QObject):
     def assignedPrinter(self):
         return self._assigned_printer
 
-    def updateAssignedPrinter(self, assigned_printer: Optional[PrinterOutputModel]):
+    def updateAssignedPrinter(self, assigned_printer: Optional["PrinterOutputModel"]):
         if self._assigned_printer != assigned_printer:
             old_printer = self._assigned_printer
             self._assigned_printer = assigned_printer
diff --git a/cura/PrinterOutput/PrinterOutputController.py b/cura/PrinterOutput/PrinterOutputController.py
index 9a29233f95..cc7b78ac11 100644
--- a/cura/PrinterOutput/PrinterOutputController.py
+++ b/cura/PrinterOutput/PrinterOutputController.py
@@ -4,7 +4,7 @@
 from UM.Logger import Logger
 from UM.Signal import Signal
 
-from typing import Any
+from typing import Union
 
 MYPY = False
 if MYPY:
@@ -15,7 +15,7 @@ if MYPY:
 
 
 class PrinterOutputController:
-    def __init__(self, output_device: PrinterOutputDevice) -> None:
+    def __init__(self, output_device: "PrinterOutputDevice") -> None:
         self.can_pause = True
         self.can_abort = True
         self.can_pre_heat_bed = True
@@ -25,7 +25,7 @@ class PrinterOutputController:
         self.can_update_firmware = False
         self._output_device = output_device
 
-    def setTargetHotendTemperature(self, printer: "PrinterOutputModel", extruder: "ExtruderOutputModel", temperature: Any[int, float]) -> None:
+    def setTargetHotendTemperature(self, printer: "PrinterOutputModel", position: int, temperature: Union[int, float]) -> None:
         Logger.log("w", "Set target hotend temperature not implemented in controller")
 
     def setTargetBedTemperature(self, printer: "PrinterOutputModel", temperature: int) -> None:
diff --git a/cura/PrinterOutput/PrinterOutputModel.py b/cura/PrinterOutput/PrinterOutputModel.py
index 96feef1b55..abfee41e80 100644
--- a/cura/PrinterOutput/PrinterOutputModel.py
+++ b/cura/PrinterOutput/PrinterOutputModel.py
@@ -172,7 +172,7 @@ class PrinterOutputModel(QObject):
     def cancelPreheatBed(self) -> None:
         self._controller.cancelPreheatBed(self)
 
-    def getController(self) -> PrinterOutputController:
+    def getController(self) -> "PrinterOutputController":
         return self._controller
 
     @pyqtProperty(str, notify=nameChanged)
@@ -205,7 +205,7 @@ class PrinterOutputModel(QObject):
         self._controller.setTargetBedTemperature(self, temperature)
         self.updateTargetBedTemperature(temperature)
 
-    def updateActivePrintJob(self, print_job: Optional[PrintJobOutputModel]) -> None:
+    def updateActivePrintJob(self, print_job: Optional["PrintJobOutputModel"]) -> None:
         if self._active_print_job != print_job:
             old_print_job = self._active_print_job
 
@@ -223,14 +223,14 @@ class PrinterOutputModel(QObject):
             self.stateChanged.emit()
 
     @pyqtProperty(QObject, notify = activePrintJobChanged)
-    def activePrintJob(self) -> Optional[PrintJobOutputModel]:
+    def activePrintJob(self) -> Optional["PrintJobOutputModel"]:
         return self._active_print_job
 
     @pyqtProperty(str, notify=stateChanged)
     def state(self) -> str:
         return self._printer_state
 
-    @pyqtProperty(int, notify = bedTemperatureChanged)
+    @pyqtProperty(int, notify=bedTemperatureChanged)
     def bedTemperature(self) -> int:
         return self._bed_temperature
 
diff --git a/plugins/USBPrinting/USBPrinterOutputDevice.py b/plugins/USBPrinting/USBPrinterOutputDevice.py
index 9ab2a06d50..ebfdca2dab 100644
--- a/plugins/USBPrinting/USBPrinterOutputDevice.py
+++ b/plugins/USBPrinting/USBPrinterOutputDevice.py
@@ -21,7 +21,7 @@ from serial import Serial, SerialException, SerialTimeoutException
 from threading import Thread, Event
 from time import time, sleep
 from queue import Queue
-from typing import Union, Optional, List, cast, Any
+from typing import Union, Optional, List, cast
 
 import re
 import functools  # Used for reduce
@@ -99,7 +99,7 @@ class USBPrinterOutputDevice(PrinterOutputDevice):
             application.triggerNextExitCheck()
 
     @pyqtSlot(str)
-    def updateFirmware(self, file: Any[str, QUrl]) -> None:
+    def updateFirmware(self, file: Union[str, QUrl]) -> None:
         self._firmware_updater.updateFirmware(file)
 
     ## Reset USB device settings