code: def encryption_mode(self):
          
  
          encryption_algo = self['algorithm'].native
  
          if encryption_algo[0:7] in set(['aes128_', 'aes192_', 'aes256_']):
              return encryption_algo[7:]
  
          if encryption_algo[0:6] == 'pbes1_':
              return 'cbc'
  
          if encryption_algo[0:7] == 'pkcs12_':
              return 'cbc'
  
          if encryption_algo in set(['des', 'tripledes_3key', 'rc2', 'rc5']):
              return 'cbc'
  
          if encryption_algo == 'pbes2':
              return self['parameters']['encryption_scheme'].encryption_mode
  
          raise ValueError(unwrap(
              '''
              Unrecognized encryption algorithm "%s"
              ''',
              encryption_algo
          ))
docs: Returns the name of the encryption mode to use.
  
          :return:
              A unicode string from one of the following: "cbc", "ecb", "ofb",
              "cfb", "wrap", "gcm", "ccm", "wrap_pad"