Field.to_representation() should accept None

[Kangaroux]

Bug report

What's wrong

The type stubs do not allow to_representation to be given None, even though this is valid.

from rest_framework import serializers
serializers.DateField(allow_null=True).to_representation(None)

mypy error:

Argument 1 to "to_representation" of "Field" has incompatible type "None"; expected "date"  [arg-type]

How is that should be

None should be a supported value type for serializers.

System information

• OS: PopOS 22.04
• python version: 3.11.4
• django version: 4.2.7
• mypy version: 1.6.1
• django-stubs version: 4.2.6

[intgr]

Agreed. Are you interested in opening a PR?

[Kangaroux]

Agreed. Are you interested in opening a PR?

Yes, I created one #511