code: def test_listing_file(path_coutwildrnp_json):
      """list layers from an open file object"""
      with open(path_coutwildrnp_json, "rb") as f:
          assert len(fiona.listlayers(f)) == 1
  
imports: from pathlib import Path
  import os
  import pytest
  import fiona
  import fiona.ogrext
  from fiona.errors import DriverError, FionaDeprecationWarning, FionaValueError
  from fiona.io import ZipMemoryFile
label_desc: Use image node_id 12 for calling a global function with example usage: test_listing_file(path_coutwildrnp_json) without return types