New issue by eoli3n on void-packages repository

https://github.com/void-linux/void-packages/issues/27242

Description:
### System

* xuname:  
  Void 5.9.14_1 x86_64 GenuineIntel/VM notuptodate rrrmFFF
* package:  
  variety-0.8.3_2

On arch, i use 0.8.5 and it works well.

### Expected behavior
Variety launching

### Actual behavior
```
Traceback (most recent call last):
  File "/bin/variety", line 66, in <module>
    variety.main()
  File "/usr/lib/python3.9/site-packages/variety/__init__.py", line 239, in main
    window.start(arguments)
  File "/usr/lib/python3.9/site-packages/variety/VarietyWindow.py", line 146, in start
    self.show_welcome_dialog()
  File "/usr/lib/python3.9/site-packages/variety/VarietyWindow.py", line 2283, in show_welcome_dialog
    dialog = WelcomeDialog()
  File "/usr/lib/python3.9/site-packages/variety/WelcomeDialog.py", line 31, in __new__
    builder = get_builder("WelcomeDialog")
  File "/usr/lib/python3.9/site-packages/variety_lib/helpers.py", line 39, in get_builder
    builder.add_from_file(ui_filename)
  File "/usr/lib/python3.9/site-packages/variety_lib/Builder.py", line 91, in add_from_file
    ele_widgets = tree.getiterator("object")
AttributeError: 'ElementTree' object has no attribute 'getiterator'
```

### Steps to reproduce the behavior
install package and run ``variety``