Created Issue: Validating dynamic attributes [7127]

hi,
awesome library, but could you tell me please how to validate the following
```
public class Product
{
public string Id { get; set; }
public List<Attribute> Attributes { get; set; }
}

public class Attribute
{
public string Name { get; set; }
public string Value { get; set; }
}
var person = new Person();
person.Attributes.Add("price","10");

```
how can i validate that price attribute is no more than 5 for example.

thanks in advanced.