Padznich python sdk anyof allof root model

[wing328]

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Summary by cubic

Upgrades the Python generator for Pydantic v2 with cleaner unions and safer file handling. anyOf/oneOf now use RootModel unions, docs and samples show v2 APIs, and file downloads strip path traversal.

• New Features

  • Generate anyOf/oneOf as Pydantic RootModel[Union[...]] for cleaner typing and validation.
  • Use Field and Literal for enums to improve type safety and IDE help.
  • Update Python docs, generator examples, and samples to model_validate(_json) and model_dump(_json) APIs.
  • Sanitize filenames from Content-Disposition with os.path.basename during file download.

• Migration

  • Replace to_json/from_json/to_dict/from_dict with:
    • model_validate_json / model_validate
    • model_dump_json(by_alias=True, exclude_unset=True) / model_dump(by_alias=True)
  • anyOf/oneOf are RootModel unions; access the wrapped value via instance.root.
  • Regenerate Python clients/servers to adopt the new templates.

^{Written for commit e8368a9. Summary will update on new commits.}