code: def groestlHash(data):
      
      try:
          import groestlcoin_hash
      except ImportError:
          t = 'Groestlcoin requires the groestlcoin_hash package ("pip install groestlcoin_hash").'
          print(t)
          raise ImportError(t)
  
      return bytes_as_revhex(groestlcoin_hash.getHash(data, len(data)))
docs: Groestl-512 compound hash.