docs: def get_package_version():
      """return package version without importing it"""
      base = os.path.abspath(os.path.dirname(__file__))
      with open(os.path.join(base, 'policy', '__init__.py'),
                mode='rt',
                encoding='utf-8') as initf:
          for line in initf:
              m = version.match(line.strip())
              if not m:
                  continue
              return m.groups()[0]