Function define_property_str 

pub fn define_property_str<T>(
    target: &Object<T>,
    property_key: &JsString,
    attributes: &PropertyDescriptor<T>,
) -> Result<bool, JsValue>
where
    Object<T>: ErasableGenericBorrow<Object<JsValue>>,
    PropertyDescriptor<T>: ErasableGenericBorrow<PropertyDescriptor<JsValue>>,

The static Reflect.defineProperty() method is like Object.defineProperty() but returns a Boolean.

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