C# XML序列化如何设置属性xsi:类型

using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;

[XmlType(TypeName = "Person", Namespace = "http://example.com")]
public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }
}

public class Program
{
    static void Main()
    {
        Person person = new Person { Name = "John", Age = 25 };

        XmlSerializer serializer = new XmlSerializer(typeof(Person));
        XmlWriterSettings settings = new XmlWriterSettings
        {
            Indent = true,
            IndentChars = "\t"
        };

        using (XmlWriter writer = XmlWriter.Create("person.xml", settings))
        {
            XmlSerializerNamespaces namespaces = new XmlSerializerNamespaces();
            namespaces.Add("xsi", "http://www.w3.org/2001/XMLSchema-instance");
            serializer.Serialize(writer, person, namespaces);
        }
    }
}

<Person xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="Person" xmlns="http://example.com">
    <Name>John</Name>
    <Age>25</Age>
</Person>