code: def parse_authority(cls, authority):
          '''Parse the authority part and return userinfo and host.'''
          userinfo, sep, host = authority.partition('@')
  
          if not sep:
              return '', userinfo
          else:
              return userinfo, hosf parse_authority(cls, authority):
          '''Parse the authority part and return userinfo and host.'''
          userinfo, sep, host = authority.partition('@')
  
          if not sep:
              return '', userinfo
          else:
              return userinfo, host
docs: Parse the authority part and return userinfo and host.