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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 __generateOTPKs(self, num_otpks = None):
 """ Generate the given amount of OTPKs. :param num_otpks: Either an integer or None. If the value of num_otpks is None, set it to the max_num_otpks value of the configuration. """


        if num_otpks == None:
            num_otpks = self.__max_num_otpks
        
        otpks = []

        for _ in range(num_otpks):
            otpks.append(self.__KeyPair.generate())

        try:
            self.__otpks.extend(otpks)
        except AttributeError:
            self.__otpks = otpks