type Preview = Pick<{ id: number; name: string; bio: string }, 'id' | 'name'>
// Preview = { id: number; name: string }Pick<T, K> constructs a new type with only the specified subset of properties from T.
Pick<T, K> constructs a type with only the properties K from T.
Challenge: Implement pickKeys<T extends object, K extends keyof T>(obj: T, keys: K[]): Pick<T, K>.
pickKeys({ a: 1, b: 2, c: 3 }, ['a', 'c']) // → { a: 1, c: 3 }