dictEx = {
   Student: [5,6]
   Student: [7,8]
   Student: [10,9]
}

class Student:
   def __init__(self, *args):
      self.__dict__ = dict(zip(['name', 'grade'], args))
   def getName(self):
      return self.name
   def __repr__(self):
      return "{}({})".format(self.__class__.__name__, ' '.join('{}:{}'.format(a, b) for a, b in self.__dict__.items()))

dictEx = {
  Student('Tom', 10): [5,6],
  Student('James', 12): [7,8],
  Student('James', 7): [10,9],
}
new_dict = sorted(dictEx.items(), key=lambda x:(x[0].getName(), x[-1]))

[(Student(grade:12 name:James), [7, 8]), (Student(grade:7 name:James), [10, 9]), (Student(grade:10 name:Tom), [5, 6])]