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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 start_time_distance(item_a, item_b, max_value):
 """ Absolute difference between the starting times of each item. Args: item_a: STObject from the first set in TrackMatcher item_b: STObject from the second set in TrackMatcher max_value: Maximum distance value used as scaling value and upper constraint. Returns: Distance value between 0 and 1. """

    start_time_diff = np.abs(item_a.times[0] - item_b.times[0])
    return np.minimum(start_time_diff, max_value) / float(max_value)