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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 get_levels(self, arcs):
 """Calculate available arc height "levels". Used to calculate arrow heights dynamically and without wasting space. args (list):
 Individual arcs and their start, end, direction and label. RETURNS (list):
 Arc levels sorted from lowest to highest. """

        levels = set(map(lambda arc: arc["end"] - arc["start"], arcs))
        return sorted(list(levels))