GCP Secret Manager Access "Invalid Grant" error 503 with Python 3.11

really losing it here. I wrote a simple piece of code just to be able to access secrets, and every time I run it it simply throws the following error:

google.api_core.exceptions.RetryError: Deadline of 60.0s exceeded while calling target function, last exception: 503 Getting metadata from plugin failed with error: ('invalid_grant: Bad Request', {'error': 'invalid_grant', 'error_description': 'Bad Request'})

Below is my code:

from google.cloud import secretmanager

def secretFinder(projectid, secretid, version):

    client = secretmanager.SecretManagerServiceClient()
    name = f"projects/{projectid}/secrets/{secretid}/versions/{version}"
    response = client.access_secret_version(name=name)
    return response.payload.data.decode('UTF-8')

secretFinder("my_project", "test", "latest")

My CLI is auth'd with my service account, which contains the following roles associated with it -

Owner
Secret Manager Admin
Secret Manager Secret Accessor

I confirmed only my account is auth'd by running 

gcloud auth list

Next, I ensured I set the correct project by running

gcloud config set project PROJECT_ID

Where project id is "my_project". I did not use the project #, but instead the actual project ID as directed. 

Ironically, if I run the following via cli I actually get my secret:

gcloud secrets versions access --secret=test latest

I truly don't know what to do at this point and any help would be greatly appreciated.

Thanks in advance!

Run gcloud auth application-default login and try again.

If that does not work, move this question to Stack Overflow. Add details on the environment you are running the code on.

Note: the CLI gcloud uses different credentials than your code. Your code is using ADC (Application Default Credentials), which is why you must authenticate using application-default command option.

Your other option is to modify your code and specify the service account as a parameter to SecretManagerServiceClient().