code: def test_returns_none_if_client_version_is_latest(
      self, server_version: Optional[str]
  ):
      res = check_client_server_compatibility(
          client_version="latest",
          server_version=server_version,
      )
      assert res is None
  
file_path: dstack/src/tests/_internal/server/utils/test_routers.py
imports: from typing import Optional
  import pytest
  from dstack._internal.server.utils.routers import check_client_server_compatibility
label_desc: Use image node_id 5 for calling the TestCheckClientServerCompatibility obj's underlying member method code with example usage: obj.test_returns_none_if_client_version_is_latest(server_version) without return types