old_contents: import sys
  import os
  from subprocess import check_call
  from pew._utils import invoke_pew as invoke
  from utils import skip_windows, connection_required
  import pytest
  
  def skip_marker(f):
      return skip_windows(reason='Pythonz unavailable in Windows')(
          pytest.mark.skipif(
              sys.platform == 'cygwin',
              reason='Pythonz unavailable in Cygwin')(
                  pytest.mark.skipif(os.environ.get('NIX'),
                                     reason='Pythonz unavailable in Nix')(
                      connection_required(f))))
  
  @skip_marker
  def test_install():
      py_version = ['2.6.1', '--type', 'pypy']
      assert invoke('install', *py_version).returncode == 0
      py = invoke('locate_python', *py_version).out
      check_call([py, '-V'])
  
  @skip_marker
  def test_uninstall():
      py_version = ['2.6.1', '--type', 'pypy']
      invoke('install', *py_version)
      assert invoke('uninstall', *py_version).returncode == 0
      assert invoke('locate_python', *py_version).returncode != 0
  
new_contents: import sys
  import os
  from subprocess import check_call
  from pew._utils import invoke_pew as invoke
  from utils import skip_windows, connection_required
  import pytest
  
  def skip_marker(f):
      return skip_windows(reason='Pythonz unavailable in Windows')(
          pytest.mark.skipif(
              sys.platform == 'cygwin',
              reason='Pythonz unavailable in Cygwin')(
                  pytest.mark.skipif(os.environ.get('NIX'),
                                     reason='Pythonz unavailable in Nix')(
                      connection_required(f))))
  
  @skip_marker
  def test_install():
      py_version = ['3.5.1']
      assert invoke('install', *py_version).returncode == 0
      py = invoke('locate_python', *py_version).out
      check_call([py, '-V'])
  
  @skip_marker
  def test_uninstall():
      py_version = ['3.5.1']
      invoke('install', *py_version)
      assert invoke('uninstall', *py_version).returncode == 0
      assert invoke('locate_python', *py_version).returncode != 0
  
subject: Replace version of Python to install in test_{un,}install test