plugin.py

class JSONSchemaPlugin(Plugin):
    """Provides support for the JSON Schema as TypedDict."""
    
    # I put the placeholder class in a package called `jsonschema_typed`.
    JSONSchema = 'jsonschema_typed.types.JSONSchema'    

    def get_type_analyze_hook(self, fullname: str) -> Optional[Callable]:
        """Produce an analyzer callback if a JSONSchema annotation is found."""
        if fullname == self.JSONSchema:
            def callback(ctx: AnalyzeTypeContext) -> TypedDictType:
                """Generate annotations from a JSON Schema."""
                ...    # Here is where we need to generate the TypedDictType.
            return callback