def decipher(self,string):
string = self.remove_punctuation(string,filter='<STR_LIT>'+self.chars+'<STR_LIT:]>')<EOL>ret = '<STR_LIT>'<EOL>for i in range(<NUM_LIT:0>,len(string),<NUM_LIT:3>):<EOL><INDENT>ind = tuple([int(string[i+k]) for k in [<NUM_LIT:0>,<NUM_LIT:1>,<NUM_LIT:2>]])<EOL>ret += IND2L[ind]<EOL><DEDENT>return ret<EOL>
Decipher string using Delastelle cipher according to initialised key.

        Example::

            plaintext = Delastelle('APCZ WRLFBDKOTYUQGENHXMIVS').decipher(ciphertext)     

        :param string: The string to decipher.
        :returns: The deciphered string. The plaintext will be 1/3 the length of the ciphertext.