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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 increase_frequency(self, frequency=None):
 """ Increases the frequency. :param frequency: the frequency to increase by, 1 if None :type frequency: int """

        if frequency is None:
            javabridge.call(self.jobject, "increaseFrequency", "()V")
        else:
            javabridge.call(self.jobject, "increaseFrequency", "(I)V", frequency)