def encipher(self,string,keep_punct=False):
if not keep_punct: string = self.remove_punctuation(string)<EOL>return '<STR_LIT>'.join(self.buildfence(string, self.key))<EOL>
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.