code: def get_scheme(cls, hashed_passord):
          
          if not hashed_passord[0] == b'{'[0] or b'}' not in hashed_passord:
              raise cls.BadHash("%r should start with the scheme enclosed with { }" % hashed_passord)
          scheme = hashed_passord.split(b'}', 1)[0]
          scheme = scheme.upper() + b"}"
          return scheme
docs: Return the scheme of ``hashed_passord`` or raise :attr:`BadHash`
  
              :param bytes hashed_passord: A hashed password
              :return: The scheme used by the hashed password
              :rtype: bytes
              :raises BadHash: if no valid scheme is found within ``hashed_passord``