code: def _get_template_dirs():
      
      return filter(lambda x: os.path.exists(x), [
          # user dir
          os.path.join(os.path.expanduser('~'), '.py2pack', 'templates'),
          # system wide dir
          os.path.join('/', 'usr', 'share', 'py2pack', 'templates'),
          # usually inside the site-packages dir
          os.path.join(os.path.dirname(os.path.abspath(__file__)), 'templates'),
      ])
docs: existing directories where to search for jinja2 templates. The order
      is important. The first found template from the first found dir wins!