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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 distant_level(reference_level, distance, reference_distance=1.0):
 """ Calculates the sound pressure level in dependence of a distance where a perfect ball-shaped source and spread is assumed. reference_level: Sound pressure level in reference distance in dB distance: Distance to calculate sound pressure level for, in meters reference_distance: reference distance in meters (defaults to 1) """

    rel_dist = float(reference_distance) / float(distance)
    level = float(reference_level) + 20.0 * (math.log(rel_dist) / math.log(10))
    return level