I have a piece of code with the output of dictionaries in a text file, and I had a question whether it can be done with the shelve module?

I have this piece of code

dict3 = {'12345': ['paper', '3'], '67890': ['pen', '78'], '11223': ['olive', '100'], '33344': ['book', 
'18']}

output = open("output.txt", "a", encoding='utf-8')
for k, v in dict3.items():
   output.writelines(f'{k} {v[0]} {v[1]}\n') 
output.close()

When this code is executed I have this result:

12345 paper 3

67890 pen 78

11223 olive 100

33344 book 18

So, maybe someone knows how to do the same, but using the shelve module?

Since shelve shelves smell like dictionaries, you can just use .update() to write that dict into a shelf, then .items() to read:

import shelve

dict3 = {
    '12345': ['paper', '3'],
    '67890': ['pen', '78'],
    '11223': ['olive', '100'],
    '33344': ['book', '18'],
}

with shelve.open("my.shelf") as shelf:
    shelf.update(dict3)

# ...

with shelve.open("my.shelf") as shelf:
    for k, v in shelf.items():
        print(k, v)

Output:

67890 ['pen', '78']
12345 ['paper', '3']
11223 ['olive', '100']
33344 ['book', '18']