Answers for "sort function in python with key"

python sort list in reverse

#1 Changes list
list.sort(reverse=True)
#2 Returns sorted list
sorted(list, reverse=True)

sort key python

>>> sorted(student_tuples, key=itemgetter(2))
[('dave', 'B', 10), ('jane', 'B', 12), ('john', 'A', 15)]

sort key python

>>> class Student:
...     def __init__(self, name, grade, age):
...         self.name = name
...         self.grade = grade
...         self.age = age
...     def __repr__(self):
...         return repr((self.name, self.grade, self.age))