python pickle module

Question

import pickle

class Cucumber:
    def __init__(self):
        self.size = 'small'

    def get_size(self):
        return self.size

cucu = Cucumber()

with open('cucumber.pckl', 'wb') as file_out:
    pickle.dump(cucu,file_out)
"""
import pickle
with open('cucumber.pckl', 'rb') as file_in:
    data = pickle.load(file_in)

print(type(data))
print(data)
print(data.size)
print(data.get_size())

"""
"""
上面那段是输入，下面那段是输出，输出的时候报错，
报错信息：data = pickle.load(file_in)
AttributeError: Can't get attribute 'Cucumber' on <module '__main__' (built-in)>
请问怎么修改
object,functions and class can be pickled, 为什么还会报错？

Answer 1

Cucumber类定义要放代码里面

import pickle
 
class Cucumber:
    def __init__(self):
        self.size = 'small'
 
    def get_size(self):
        return self.size
 
#cucu = Cucumber()
 
#with open('cucumber.pckl', 'wb') as file_out:
#    pickle.dump(cucu,file_out)


import pickle
with open('cucumber.pckl', 'rb') as file_in:
    data = pickle.load(file_in)
print(type(data))
print(data)
print(data.size)
print(data.get_size())