var arr = [      {name:"Grace", age: "28"},      {name:"Peter", age: "15"},      {name:"Grace", age: "28"},      {name:"John", age: "16"},      {name:"Prince", age: "19"},      {name:"John", age: "16"}    ]; 我現(xiàn)在只想返回那些獨(dú)特的如下var new = [  {name:"Peter", age: "15"},  {name:"Prince", age: "19"},];