#sorts multiple strings
class Student:
        def __init__(self, name, grade, group):
            self.name = name
            self.grade = grade
            self.group = group
        def __repr__(self):
            return repr((self.name, self.grade, self.group))
student_tuples = [
    Student("dave", 12, "ClassA"),
    Student("Jon", 3, "ClassA"),
    Student("Tony", 4, "ClassA"),
    ]
b = sorted (student_tuples, key=lambda student:student.grade)
 
print (b)
 
 

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