code: def source_date_year(request, monkeypatch):
      sde = request.param
      with monkeypatch.context() as m:
          if sde:
              m.setenv("SOURCE_DATE_EPOCH", str(sde))
              yield time.gmtime(sde).tm_year
          else:
              m.delenv("SOURCE_DATE_EPOCH", raising=False)
              yield None
  
imports: import pickle
  import time
  from pathlib import Path
  from unittest import mock
  import pytest
  import sphinx
  from sphinx.builders.gettext import _gettext_compact_validator
  from sphinx.config import ENUM, Config, _Opt, check_confval_types
  from sphinx.deprecation import RemovedInSphinx90Warning
  from sphinx.errors import ConfigError, ExtensionError, VersionRequirementError
label_desc: Use image node_id 31 for calling a global function with example usage: source_date_year(request, monkeypatch) without return types