interface Person {
name: string;
age: number;
}
type K1 = keyof Person; // "name" | "age"
type K2 = keyof Person[]; // "length" | "toString" | "pop" | "push" | "concat" | "join"
type K3 = keyof { [x: string]: Person }; // string | number
初学ts,K3的类型为什么是 string | number,K1和K2都理解,K3中keyof后的对象代表什么意思呢,求解答