old_contents: import pytest
  from os.path import abspath, basename, dirname, join
  import subprocess
  import glob
  import sys
  
  
  cwd = abspath(dirname(__file__))
  examples_dir = join(cwd, "..", "..", "examples")
  example_files = glob.glob("%s/*.py" % examples_dir)
  
  
  @pytest.fixture(params=[f for f in example_files], ids=lambda x: basename(x))
  def example_file(request):
      return abspath(request.param)
  
  
  def test_example_runs(example_file, tmpdir, monkeypatch):
      # This ensures that the test writes output in a temporary
      # directory, rather than where pytest was run from.
      monkeypatch.chdir(tmpdir)
      subprocess.check_call([sys.executable, example_file, "--running-tests"])
  
new_contents: import pytest
  from os.path import abspath, basename, dirname, join
  import subprocess
  import glob
  import sys
  
  
  cwd = abspath(dirname(__file__))
  examples_dir = join(cwd, "..", "..", "examples")
  example_files = glob.glob("%s/*.py" % examples_dir)
  
  
  @pytest.fixture(params=[pytest.param(f, marks=pytest.mark.xfail(reason="unreliable")) if f.endswith("mountain_hydrostatic.py") else f for f in example_files],
                  ids=lambda x: basename(x))
  def example_file(request):
      return abspath(request.param)
  
  
  def test_example_runs(example_file, tmpdir, monkeypatch):
      # This ensures that the test writes output in a temporary
      # directory, rather than where pytest was run from.
      monkeypatch.chdir(tmpdir)
      subprocess.check_call([sys.executable, example_file, "--running-tests"])
  
subject: update test_examples file for more graceful xfail