### Breaking Changes

* PR [#2434](https://github.com/tiangolo/fastapi/pull/2434) includes several improvements that shouldn't affect normal use cases, but could affect in advanced scenarios:
    * If you are testing the generated OpenAPI (you shouldn't, FastAPI already tests it extensively for you): the order for `tags` in `include_router` and *path operations* was updated for consistency, but it's a simple order change.

type Constraint ~int         // illegal: ~int is not in a type parameter list
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We should be able to simplify the rules for comparable or delegate some of them
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<p>
The <a href="#Predeclared_identifiers">predeclared</a>