code: def _warn_incompatibility_with_xunit2(request, fixture_name):
      """Emits a PytestWarning about the given fixture being incompatible with newer xunit revisions"""
      from _pytest.warning_types import PytestWarning
  
      xml = getattr(request.config, "_xml", None)
      if xml is not None and xml.family not in ("xunit1", "legacy"):
          request.node.warn(
              PytestWarning(
                  "{fixture_name} is incompatible with junit_family '{family}' (use 'legacy' or 'xunit1')".format(
                      fixture_name=fixture_name, family=xml.family
                  )
              )
          )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import functools
  import os
  import platform
  import re
  import sys
  import time
  from datetime import datetime
  import py
  import six
  import pytest
  from _pytest import nodes
  from _pytest.config import filename_arg
label_desc: Use image node_id 3 for calling a global function with example usage: _warn_incompatibility_with_xunit2(request, fixture_name) without return types