.update(id: string, data: any)

// load data
const data = {
    instruments = await new InstrumentModel().load()
};

// update an instrument
data.instruments.update(
    '8d961961-6323-48b3-b4b4-849daa1ac3ed',
    {
        name: 'Trombone',
        type: 'brass'
    }
);