code: def decipher(self,string):
                             
          string = string.upper()
          mapping = dict(zip(self.key,self.table))
          ptext = ""
          for i in string:
              ptext += mapping[i]
          return self.demorse(ptext)
docs: Decipher string using FracMorse cipher according to initialised key. 
  
          Example::
  
              plaintext = FracMorse('ROUNDTABLECFGHIJKMPQSVWXYZ').decipher(ciphertext)     
  
          :param string: The string to decipher.
          :returns: The enciphered string.