code: def test_serve_get_actor():
      runner = CliRunner()
      result = runner.invoke(
          cli,
          [
              "serve",
              "--memory",
              "--get",
              "/-/actor.json",
              "--actor",
              '{"id": "root", "extra": "x"}',
          ],
          catch_exceptions=False,
      )
      assert result.exit_code == 0
      assert json.loads(result.output) == {
          "actor": {
              "id": "root",
              "extra": "x",
          }
      }
  
file_path: datasette/tests/test_cli_serve_get.py
imports: from datasette.cli import cli, serve
  from datasette.plugins import pm
  from click.testing import CliRunner
  import textwrap
  import json
label_desc: Use image node_id 4 for calling a global function with example usage: test_serve_get_actor() without return types