python uuid doesn't give me unique identifiers?

Question

I have this function in python that reads in a dict and is supposed to loop a number of times then give my a set of unique ids into a dict.

import uuid
import time

def generate_cluster_group(template: dict, number: int):
    for i in range(number):
        time.sleep(1)
        if i == 0:
            instance = template
            id_ = uuid.uuid4()
            instance['id'] = str(id_)
            virtualInstances = [template]
        else:
            ninstance = template
            id_ = uuid.uuid4()
            ninstance['id'] = str(id_)
            virtualInstances.append(ninstance)
            
    return virtualInstances

sample_template = {'id': 'none'}

result = generate_cluster_group(sample_template, 3)

### desired result
result = [{'id': 'fe918527-5f27-4333-a8ec-887d755a4002'},
          {'id': '8b97fc31-2e01-4949-8eca-954583f4b8fe'},
          {'id': '5fb021e8-d15d-453c-a8c0-9327e7c88634'}]

but I end up with the same id duplicated

actual_result = [{'id': 'fe918527-5f27-4333-a8ec-887d755a4002'},
          {'id': 'fe918527-5f27-4333-a8ec-887d755a4002'},
          {'id': 'fe918527-5f27-4333-a8ec-887d755a4002'}]

am I misunderstanding how the uuid function works?

the sample template is fed into the generate_cluster_group function. Is it defined as a dict. See the second block of code — KillerSnail, Jul 10 '20 at 14:26
You keep using the same instance of `dict`, the one supplied as a parameter. — quamrana, Jul 10 '20 at 14:27
See https://stackoverflow.com/questions/2465921/how-to-copy-a-dictionary-and-only-edit-the-copy — DeepSpace, Jul 10 '20 at 14:27

score 0 · Answer 1 · answered Jul 10 '20 at 14:31

You are making several mistakes in your function. It could be simplified to this:

def generate_cluster_group(template: dict, number: int):
    virtualInstances = []
    for _ in range(number):
        time.sleep(1)
        ninstance = dict(template)
        ninstance['id'] = str(uuid.uuid4())
        virtualInstances.append(ninstance)
            
    return virtualInstances

python uuid doesn't give me unique identifiers?

1 Answers1