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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 continuous_frequency(self, data_frame):
 """ This method returns continuous frequency :param data_frame: the data frame :type data_frame: pandas.DataFrame :return cont_freq: frequency :rtype cont_freq: float """

        tap_timestamps = data_frame.td[data_frame.action_type==1]
        cont_freq = 1.0/(np.array(tap_timestamps[1:-1])-np.array(tap_timestamps[0:-2]))
        duration = math.ceil(data_frame.td[-1])

        return cont_freq, duration