code: function _ensureArray (model, property) {
    const propertyKey = property.getKey();
    let array = model.data[propertyKey];
    if (!array) {
      model.data[propertyKey] = array = [];
      ArrayType.flagAsArrayType(array);
    }
  
    return array;
  }
docs: This function will be used to make sure an array value exists for the given property