I call api and have an object:

    const body = { 
    data:{ 
        book: 
        [ { "name": "math", "class": 8, "level": 2 },
          { "name": "math", "class": 10, "level": 2} 
        ]
     }
 }

Now I want to get an array

 [ { "name": "math", "class": 8, "level": 2 },
   { "name": "math", "class": 10, "level": 2} 
 ] 

But I get const books = body.data.book and console.log(books) and I have an undefined book. You can help me?