sort objects by multiple keys

In [50]: students =[
 {'name': 'Paul Allen', 'class': 'Science', 'grade': 'A'},
 {'name': 'paul allen', 'class': 'Math', 'grade': 'C'},
 {'name': 'Bob Lewis', 'class': 'Science', 'grade': 'D'},
 {'name': 'Bob Lewis', 'class': 'math', 'grade': 'b'},
 {'name': 'bob Lewis', 'class': 'History', 'grade': 'f'}
]

In [52]: sorted(students)                                                                                                                                                                                          
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-52-7d3dd5d8afa9> in <module>
----> 1 sorted(students)

TypeError: '<' not supported between instances of 'dict' and 'dict'

In [53]: sorted(students, key=lambda k: k['name'])                                                                                                                                                                 
Out[53]: 
[{'name': 'Bob Lewis', 'class': 'Science', 'grade': 'D'},
 {'name': 'Bob Lewis', 'class': 'math', 'grade': 'b'},
 {'name': 'Paul Allen', 'class': 'Science', 'grade': 'A'},
 {'name': 'bob Lewis', 'class': 'History', 'grade': 'f'},
 {'name': 'paul allen', 'class': 'Math', 'grade': 'C'}]

In [54]: sorted(students, key=lambda k: (k['name'], k['grade']))                                                                                                                                                   
Out[54]: 
[{'name': 'Bob Lewis', 'class': 'Science', 'grade': 'D'},
 {'name': 'Bob Lewis', 'class': 'math', 'grade': 'b'},
 {'name': 'Paul Allen', 'class': 'Science', 'grade': 'A'},
 {'name': 'bob Lewis', 'class': 'History', 'grade': 'f'},
 {'name': 'paul allen', 'class': 'Math', 'grade': 'C'}]

In [55]: sorted(students, key=lambda k: (k['name'].lower(), k['grade'].lower()))                                                                                                                                   
Out[55]: 
[{'name': 'Bob Lewis', 'class': 'math', 'grade': 'b'},
 {'name': 'Bob Lewis', 'class': 'Science', 'grade': 'D'},
 {'name': 'bob Lewis', 'class': 'History', 'grade': 'f'},
 {'name': 'Paul Allen', 'class': 'Science', 'grade': 'A'},
 {'name': 'paul allen', 'class': 'Math', 'grade': 'C'}]