code: def install_virtualenv_p2(root, python_version):
      
      try:
          import virtualenv
      except ImportError:
          sys.stdout.write('Installing virtualenv into global interpreter \n')
          ret_code = subprocess.call([VE_GLOBAL_SCRIPT, PROJECT_ROOT])
          sys.stdout.write('Installation finished with code {0}. Re-run ./launch.py install \n'.format(ret_code))
          sys.exit(ret_code)
  
      if path.exists(root):
          shutil.rmtree(root)
      virtualenv.logger = virtualenv.Logger(consumers=[])
      virtualenv.create_environment(root, site_packages=False)
      ret_code = subprocess.call([VE_SCRIPT, PROJECT_ROOT, root, python_version])
      sys.exit(ret_code)
docs: Install virtual environment for Python 2.7+; removing the old one if it exists