如何仅为serde_json实现自定义序列化？

use serde::{Serialize, Deserialize};

#[derive(Serialize, Deserialize)]
struct Person {
    name: String,
    age: u32,
}

impl Serialize for Person {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: serde::Serializer,
    {
        let mut state = serializer.serialize_struct("Person", 2)?;
        state.serialize_field("name", &self.name)?;
        state.serialize_field("age", &self.age)?;
        state.end()
    }
}

impl<'de> Deserialize<'de> for Person {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::Deserializer<'de>,
    {
        struct PersonVisitor;

        impl<'de> serde::de::Visitor<'de> for PersonVisitor {
            type Value = Person;

            fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
                formatter.write_str("struct Person")
            }

            fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
            where
                A: serde::de::SeqAccess<'de>,
            {
                let name = seq.next_element()?.ok_or_else(|| serde::de::Error::invalid_length(0, &self))?;
                let age = seq.next_element()?.ok_or_else(|| serde::de::Error::invalid_length(1, &self))?;
                Ok(Person { name, age })
            }
        }

        deserializer.deserialize_struct("Person", &["name", "age"], PersonVisitor)
    }
}

fn main() {
    let person = Person {
        name: "John".to_string(),
        age: 30,
    };

    let json = serde_json::to_string(&person).unwrap();
    println!("Serialized: {}", json);

    let deserialized: Person = serde_json::from_str(&json).unwrap();
    println!("Deserialized: {:?}", deserialized);
}