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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 incoordination_score(self, data_frame):
 """ This method calculates the variance of the time interval in msec between taps :param data_frame: the data frame :type data_frame: pandas.DataFrame :return is: incoordination score :rtype is: float """

        diff = data_frame.td[1:-1].values - data_frame.td[0:-2].values
        inc_s = np.var(diff[np.arange(1, len(diff), 2)], dtype=np.float64) * 1000.0
        duration = math.ceil(data_frame.td[-1])
        return inc_s, duration