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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 Enigma M3 cipher according to initialised key. Punctuation and whitespace are removed from the input. Example:: ciphertext = Enigma(settings=('A','A','A'),rotors=(1,2,3),reflector='B', ringstellung=('F','V','N'),steckers=[('P','O'),('M','L'), ('I','U'),('K','J'),('N','H'),('Y','T'),('G','B'),('V','F'), ('R','E'),('D','C')])).encipher(plaintext) :param string: The string to encipher. :returns: The enciphered string. """
       
        string = self.remove_punctuation(string)
        ret = ''
        for c in string.upper():
            if c.isalpha(): ret += self.encipher_char(c)
            else: ret += c
        return ret