import json
class Student(object):
def __init__(self, name, age, score):
self.name = name
self.age = age
self.score = score
s = Student(‘Bob‘, 20, 88)
print(json.dumps(s))

def student2dict(std):
return {
‘name‘: std.name,
‘age‘: std.age,
‘score‘: std.score
}

>>> print(json.dumps(s, default=student2dict))
{"age": 20, "name": "Bob", "score": 88}

print(json.dumps(s, default=lambda obj: obj.__dict__))