PydanticUserError: unique_items removed use Set instead

[reisman234]

I currently create from a OpenApi Specification, the Python Models. To do this, I use the datamodel-codegen Tool.

Now the problem is on start up of the final application which uses the generated models, a PydanticError is raised.

workflow-provisioner  |   File "/opt/middlelayer/edc/connector.py", line 5, in <module>
workflow-provisioner  |     from .management_api import TransferProcessDto, ContractAgreementDto
workflow-provisioner  |   File "/opt/middlelayer/edc/management_api.py", line 44, in <module>
workflow-provisioner  |     class CallbackAddress(BaseModel):
workflow-provisioner  |   File "/opt/middlelayer/edc/management_api.py", line 47, in CallbackAddress
workflow-provisioner  |     events: Optional[List[str]] = Field(None, unique_items=True)
workflow-provisioner  |   File "/opt/.venv/lib/python3.8/site-packages/pydantic/fields.py", line 739, in Field
workflow-provisioner  |     raise PydanticUserError(
workflow-provisioner  | pydantic.errors.PydanticUserError: `unique_items` is removed, use `Set` instead(this feature is discussed in https://github.com/pydantic/pydantic-core/issues/296)
workflow-provisioner  | 
workflow-provisioner  | For further information visit https://errors.pydantic.dev/2.0.3/u/removed-kwargs
workflow-provisioner  | 

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This is the command I used to generate the model, with some warning messages:

(.venv) ralph@thinkpad-l580:~/.../cloud-scheduling-edc/gx4ki-provisioner$ datamodel-codegen --input-file-type openapi --use-unique-items-as-set --target-python-
version 3.8  --input ~/Downloads/eclipse-edc-bot-management-api-0.1.1-SNAPSHOT-swagger.json --output  middlelayer/edc/management-api_3.8.py
/home/ralph/Documents/hso/gaiax4ki/ap2.1/cloud-scheduling-edc/gx4ki-provisioner/.venv/lib/python3.8/site-packages/pydantic/main.py:309: UserWarning: Pydantic serializer warnings:
  Expected `Union[list[definition-ref], definition-ref, bool]` but got `JsonSchemaObject` - serialized value may not be as expected
  return self.__pydantic_serializer__.to_python(
/home/ralph/Documents/hso/gaiax4ki/ap2.1/cloud-scheduling-edc/gx4ki-provisioner/.venv/lib/python3.8/site-packages/datamodel_code_generator/parser/jsonschema.py:339: UserWarning: format of 'url' not understood for 'string' - using default
  warn(
/home/ralph/Documents/hso/gaiax4ki/ap2.1/cloud-scheduling-edc/gx4ki-provisioner/.venv/lib/python3.8/site-packages/pydantic/main.py:309: UserWarning: Pydantic serializer warnings:
  Expected `Union[list[definition-ref], definition-ref, bool]` but got `JsonSchemaObject` - serialized value may not be as expected
  Expected `Union[definition-ref, bool]` but got `JsonSchemaObject` - serialized value may not be as expected
  Expected `Union[definition-ref, bool]` but got `JsonSchemaObject` - serialized value may not be as expected
  return self.__pydantic_serializer__.to_python(

After I got notice of the --use-unique-items-as-set switch, I used that also, but it does not resolve the problem.

The question is therefore, why does the tool add the unique_item=True parameter when generating the code, although the "use_set" switch is set, and it is also not allowed by the Pydantic version. Is it possible that my Python environment is broken, or is the OpenApi schema used not valid and therefore produces broken code?

[reisman234]

Finally, I found the switch which is required to generate the proper Code for the target environment.
I had to add --output-model-type pydantic_v2.BaseModel