# API Notes: CoreServices/Metadata framework

## Apple documentation

The full API is described in Apple’s documentation, both the C and Objective-C APIs are available (but see the API Notes below).

## API Notes

The Metadata framework is a subframework of CoreServices, use `import CoreServices` to access the definitions in this framework.

PyObjC provides only limited access to definitions in the framework, primarily funcionility that cannot be accessed in a better (modern) way.

The APIs to implement metadata importers is not available to python at this time.

- MDQuerySetCreateResultFunction: The CFArrayCallbacks argument must be None

- MDQuerySetCreateValueFunction: The CFArrayCallbacks argument must be None