code: def encipher(self,string,keep_punct=False):
                  
          if not keep_punct: string = self.remove_punctuation(string)
          return ''.join(self.buildfence(string, self.key))
docs: Encipher string using Railfence cipher according to initialised key.
  
          Example::
          
              ciphertext = Railfence(3).encipher(plaintext)     
  
          :param string: The string to encipher.
          :param keep_punct: if true, punctuation and spacing are retained. If false, it is all removed. Default is False. 
          :returns: The enciphered string.