#35915: QueryDict __getitem__ returns list which is surpising
-------------------------------------+-------------------------------------
     Reporter:  Nguyễn Hồng Quân     |                     Type:
                                     |  Cleanup/optimization
       Status:  new                  |                Component:  HTTP
                                     |  handling
      Version:  5.1                  |                 Severity:  Normal
     Keywords:  querydict            |             Triage Stage:
                                     |  Unreviewed
    Has patch:  0                    |      Needs documentation:  0
  Needs tests:  0                    |  Patch needs improvement:  0
Easy pickings:  0                    |                    UI/UX:  0
-------------------------------------+-------------------------------------
 Though [https://docs.djangoproject.com/en/5.1/ref/request-
 response/#django.http.QueryDict.__getitem__ 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:

 {{{#!python
 >>> 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).
-- 
Ticket URL: <https://code.djangoproject.com/ticket/35915>
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