(self, mod_base, exponent=None)
:param exponent: int
        :param mod_base: int
def __init__(self, mod_base, exponent=None):
        """

        :param exponent: int
        :param mod_base: int
        """
        super(PohligHellmanCipherKey, self).__init__()
        self.mod_base = mod_base    # p
        if exponent is not None and gcd(exponent, mod_base - 1) != 1:
            raise ValueError("In Pohlig, exponent and the totient of the modulo base must be coprimes")
        self.exponent = exponent    # a
        self.exponent_inverse = None if exponent is None else invert(exponent, mod_base - 1)
def __init__ ( self , mod_base , exponent = None ) : super ( PohligHellmanCipherKey , self ) . __init__ ( ) self . mod_base = mod_base # p if exponent is not None and gcd ( exponent , mod_base - 1 ) != 1 : raise ValueError ( "In Pohlig, exponent and the totient of the modulo base must be coprimes" ) self . exponent = exponent # a self . exponent_inverse = None if exponent is None else invert ( exponent , mod_base - 1 )