code: def test_defaults():
      sec = Security()
      assert sec.require_encryption in (None, False)
      assert sec.tls_ca_file is None
      assert sec.tls_ciphers is None
      assert sec.tls_client_key is None
      assert sec.tls_client_cert is None
      assert sec.tls_scheduler_key is None
      assert sec.tls_scheduler_cert is None
      assert sec.tls_worker_key is None
      assert sec.tls_worker_cert is None
      assert sec.tls_min_version is ssl.TLSVersion.TLSv1_2
      assert sec.tls_max_version is None
      assert sec.extra_conn_args == {}
  
imports: from __future__ import annotations
  import ssl
  from contextlib import contextmanager
  import pytest
  import dask
  from distributed.comm import connect, listen
  from distributed.security import Security
  from distributed.utils_test import gen_test, get_cert, xfail_ssl_issue5601
label_desc: Use image node_id 1 for calling a global function with example usage: test_defaults() without return types