def serialize_enums_using_as_json?
      if @serialize_enums_using_as_json.nil?
        StoreModel.config.serialize_enums_using_as_json || false
      else
        @serialize_enums_using_as_json
      end
    end
Returns the value of the `@serialize_enums_using_as_json` instance
variable. The default value is the value of the globally configured
`serialize_enums_using_as_json` option.

This method is used to determine whether enums should be serialized
when the `as_json` method is called in nested StoreModel::Model
objects.

@return [Boolean]