}
  }

  /**
   * Returns a new {@link TypeVariable} that belongs to {@code declaration} with {@code name} and
   * {@code bounds}.
   */
  static <D extends GenericDeclaration> TypeVariable<D> newArtificialTypeVariable(
      D declaration, String name, Type... bounds) {
    return newTypeVariableImpl(
        declaration, name, (bounds.length == 0) ? new Type[] {Object.class} : bounds);
  }

    }
  }

  /**
   * Returns a new {@link TypeVariable} that belongs to {@code declaration} with {@code name} and
   * {@code bounds}.
   */
  static <D extends GenericDeclaration> TypeVariable<D> newArtificialTypeVariable(
      D declaration, String name, Type... bounds) {
    return newTypeVariableImpl(
        declaration, name, (bounds.length == 0) ? new Type[] {Object.class} : bounds);
  }

         * TypeVariable to be equal to any _other_ JDK TypeVariable, either, because any other JDK
         * TypeVariable must have a different declaration or name. The only TypeVariable that our
         * new TypeVariable _will_ be equal to is an equivalent TypeVariable that was also created
         * by us. And that equality is guaranteed to hold because it doesn't involve the JDK

         * TypeVariable to be equal to any _other_ JDK TypeVariable, either, because any other JDK
         * TypeVariable must have a different declaration or name. The only TypeVariable that our
         * new TypeVariable _will_ be equal to is an equivalent TypeVariable that was also created
         * by us. And that equality is guaranteed to hold because it doesn't involve the JDK

    * Add support for type annotations using `Optional` as in `param: Optional[str] = None`. New documentation: [Optional type declarations](https://fastapi.tiangolo.com/tutorial/query-params/#optional-type-declarations).
    * PR [#278](https://github.com/tiangolo/fastapi/pull/278).

## 0.26.0

* Separate error handling for validation errors.