conditionable_type:
  type: string
  enum:
    - AlertField
  nullable: true

TypeError: Unexpected value None. Expected one of {'AlertField'}

_conditionable_type = d.pop("conditionable_type", UNSET)
conditionable_type: SomeEnumType | Unset  # Missing `| None`
if isinstance(_conditionable_type, Unset):
    conditionable_type = UNSET
else:
    # Passes None directly to check function - FAILS
    conditionable_type = check_some_enum_type(_conditionable_type)

def _parse_conditionable_type(data: object) -> SomeEnumType | None | Unset:
    if data is None:
        return data
    if isinstance(data, Unset):
        return data
    return check_some_enum_type(data)

conditionable_type = _parse_conditionable_type(d.pop("conditionable_type", UNSET))

unchecked_value_list = [value for value in enum if value is not None]

openapi: "3.0.3"
info:
  title: Test
  version: "1.0"
paths: {}
components:
  schemas:
    TestModel:
      type: object
      properties:
        my_enum:
          type: string
          enum:
            - value1
          nullable: true

from my_client.models import TestModel
TestModel.from_dict({"my_enum": None})  # Raises TypeError