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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def encipher(self,string):
 """Encipher string using Delastelle cipher according to initialised key. Example:: ciphertext = Delastelle('APCZ WRLFBDKOTYUQGENHXMIVS').encipher(plaintext) :param string: The string to encipher. :returns: The enciphered string. The ciphertext will be 3 times the length of the plaintext. """
           
        string = self.remove_punctuation(string,filter='[^'+self.key+']')        
        ctext = ""
        for c in string:
            ctext += ''.join([str(i) for i in L2IND[c]])
        return ctext