ImportError: cannot import name 'Set' from 'collections'

There seems to be a package import error in your code, making me unable to use your package.

I installed the package like below
```
pip install allcities
```

Encountered the exception below
```
PS C:\Users\3NR1QUE> python
Python 3.12.3 (tags/v3.12.3:f6650f9, Apr 9 2024, 14:05:25) [MSC v.1938 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from allcities import cities
Traceback (most recent call last):
File "", line 1, in
File "C:\Python312\Lib\site-packages\allcities\__init__.py", line 14, in
from .core import all_cities as cities
File "C:\Python312\Lib\site-packages\allcities\core.py", line 18, in
from allcities.cityset import CitySet
File "C:\Python312\Lib\site-packages\allcities\cityset.py", line 4, in
from collections import Set
ImportError: cannot import name 'Set' from 'collections' (C:\Python312\Lib\collections\__init__.py)
>>>
```