如何解决解析错误请求https://api.parse.com/1/login 400（请求错误）？

我的代码在下面，你能帮我查一下吗？ 这是给出的起始代码，它应该是一个为用户注册的函数：

function signUpUser() 
{
    //alert("clicked button");
    //creates new Parse user to be saved to database 
    var user = new Parse.User();

    //grabs the information from our form using jQuery
    var username = $("#loginInput").val();
    var password = $("#password").val();

    //sets the username and password for the User 
    user.set("username", username.toString());
    user.set("password", password.toString());

    //can add extra information to user, attributes do not have to be defined beforehand 
    user.set("favoriteColor", $("#favCol").val());
    //user.set("website", "http://www.google.com");
    //user.set("email", "email@example.com");

    //call signup function to add user to database 
    user.signUp(null, 
    {
      success: function(user)
      {
        // Hooray! Let them use the app now.
          alert("Successful Signup, you are now logged in"); 
          user.logIn(); //sets Parse.User.currentUser() to be the user variable 
      },
      error: function(user, error) 
      {
        // Show the error message somewhere and let the user try again.
        alert("Error: " + error.code + " " + error.message);
      }
    });//close user.signup 
} //closes signUpUser function