async def post(self,body: SchemaExtension, request_configuration: Optional[RequestConfiguration[QueryParameters]] = None) -> Optional[SchemaExtension]:
        """
        Create a new schemaExtension definition and its associated schema extension property to extend a supporting resource type. Schema extensions let you add strongly-typed custom data to a resource. The app that creates a schema extension is the owner app. Depending on the state of the extension, the owner app, and only the owner app, may update or delete the extension.  See examples of how to define a schema extension that describes a training course, use the schema extension definition to create a new group with training course data, and add training course data to an existing group.
        param body: The request body
        param request_configuration: Configuration for the request such as headers, query parameters, and middleware options.
        Returns: Optional[SchemaExtension]
        Find more info here: https://learn.microsoft.com/graph/api/schemaextension-post-schemaextensions?view=graph-rest-1.0
        """
        if body is None:
            raise TypeError("body cannot be null.")
        request_info = self.to_post_request_information(
            body, request_configuration
        )
        from ..models.o_data_errors.o_data_error import ODataError

        error_mapping: dict[str, type[ParsableFactory]] = {
            "XXX": ODataError,
        }
        if not self.request_adapter:
            raise Exception("Http core is null") 
        from ..models.schema_extension import SchemaExtension

        return await self.request_adapter.send_async(request_info, SchemaExtension, error_mapping)

        Create a new schemaExtension definition and its associated schema extension property to extend a supporting resource type. Schema extensions let you add strongly-typed custom data to a resource. The app that creates a schema extension is the owner app. Depending on the state of the extension, the owner app, and only the owner app, may update or delete the extension.  See examples of how to define a schema extension that describes a training course, use the schema extension definition to create a new group with training course data, and add training course data to an existing group.
        param body: The request body
        param request_configuration: Configuration for the request such as headers, query parameters, and middleware options.
        Returns: Optional[SchemaExtension]
        Find more info here: https://learn.microsoft.com/graph/api/schemaextension-post-schemaextensions?view=graph-rest-1.0
        
msgraph/generated/schema_extensions/schema_extensions_request_builder.py