code: def nybb_filename() -> str:
      # skip if data missing, unless on github actions
      if os.path.isfile(_NYBB[len("zip://") :]) or os.getenv(
          "GITHUB_ACTIONS"
      ):
          return _NYBB
      else:
          pytest.skip("NYBB dataset not found")
  
file_path: geopandas/geopandas/conftest.py
imports: import os.path
  import pytest
  import geopandas
  from geopandas.tests.util import _NYBB, _NATURALEARTH_LOWRES, _NATURALEARTH_CITIES
label_desc: Use image node_id 4 for calling a global function with example usage: nybb_filename() and returns: _NYBB