code: def test_storage_instances(db):
      studies = dft.get_studies(data_dir)
      sis = studies[0].series[0].storage_instances
      assert len(sis) == 2
      assert sis[0].instance_number == 1
      assert sis[1].instance_number == 2
      assert (
          sis[0].uid
          == "1.3.12.2.1107.5.2.32.35119.2010011420300180088599504.0"
      )
      assert (
          sis[1].uid
          == "1.3.12.2.1107.5.2.32.35119.2010011420300180088599504.1"
      )
  
imports: import os
  import sqlite3
  from io import BytesIO
  from os.path import dirname
  from os.path import join
  from ..testing import suppress_warnings
  import unittest
  import pytest
  from ..None import nifti1
  from ..optpkg import optional_package
label_desc: Use image node_id 6 for calling a global function with example usage: test_storage_instances(db) without return types