code: def test_set_dataset_id_existing(self):
      datasets = self.api_workflow_client.get_all_datasets()
      self.api_workflow_client.dataset_id = datasets[1].id
  
file_path: lightly/tests/api_workflow/test_api_workflow.py
imports: import os
  from unittest import mock
  import numpy
  import lightly
  from tests.api_workflow import utils
  from tests.api_workflow.mocked_api_workflow_client import MockedApiWorkflowClient, MockedApiWorkflowSetup
label_desc: Use image node_id 7 for calling the TestApiWorkflow obj's underlying member method code with example usage: obj.test_set_dataset_id_existing() without return types