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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 new_histogram(name, reservoir=None):
 """ Build a new histogram metric with a given reservoir object If the reservoir is not provided, a uniform reservoir with the default size is used """


    if reservoir is None:
        reservoir = histogram.UniformReservoir(histogram.DEFAULT_UNIFORM_RESERVOIR_SIZE)

    return new_metric(name, histogram.Histogram, reservoir)