code: def test_unlock_unlocked_raises():
      lock = Lock("lock")
      with pytest.raises(
          DvcException, match="Unlock called on an unlocked lock"
      ):
          lock.unlock()
  
file_path: dvc/tests/func/test_lock.py
imports: import pytest
  from dvc.cli import main
  from dvc.exceptions import DvcException
  from dvc.lock import Lock, LockError
label_desc: Use image node_id 3 for calling a global function with example usage: test_unlock_unlocked_raises() without return types