def METHOD_NAME(index):
   file_list = os.listdir('keystore/eth')
   if 'index.json' in file_list:
       file_list.remove('index.json')
   f = file_list[index]
   with open('keystore/eth/{}'.format(f)) as keyfile:
      content = json.loads(keyfile.read())
   return Web3.toChecksumAddress(content['address'])