code: def guest_mock_user(root_verify_key, user_stash, guest_user):
      result = user_stash.partition.set(root_verify_key, guest_user)
      assert result.is_ok()
  
      user = result.ok()
      assert user is not None
  
      return user
  
file_path: PySyft/packages/syft/tests/syft/service_permission_test.py
imports: import pytest
  from syft import SyftError
  from syft.client.api import SyftAPICall
label_desc: Use image node_id 1 for calling a global function with example usage: guest_mock_user(root_verify_key, user_stash, guest_user) and returns: user