QueryDict __getitem__ returns list which is surpising

[Nguyễn Hồng Quân]

Though ​documentation says that

QueryDict.__getitem__(key)
Returns the value for the given key. If the key has more than one value, it returns the last value.

It returns a list when the raw value is an empty list:

>>> from django.http import QueryDict
>>> q = QueryDict('a=1', mutable=True)
>>> q['a']
'1'

>>> q.setlist('b', [])
>>> q['b']
[]

which surprises user and it even not mentioned in documentation.

Could we change this behavior? I know that we don't have a perfect solution, but returning None in this case is less bad than empty list [], because it is easier to annotate type.

• If returns None, we can annotate type as str | None.
• If returns [], Python doesn't have an exact type for empty list, and django-stubs has to annotate as str | list[object] which is quite broader than the actual value (empty list).